Infertility
Number: 0327
Table Of Contents
PolicyApplicable CPT / HCPCS / ICD-10 Codes
Background
References
Policy
Scope of Policy
This Clinical Policy Bulletin addresses services for the management of infertility for commercial medical plans. For Medicare criteria, see Medicare Part B Criteria.
The American Society for Reproductive Medicine (ASRM, 2023) has defined infertility as a "disease, condition, or status characterized by the inability to achieve a successful pregnancy based on a patient’s medical, sexual, and reproductive history, age, physical findings, diagnostic testing, or any combination of those factors; or the need for medical intervention, including, but not limited to, the use of donor gametes or donor embryos in order to achieve a successful pregnancy either as an individual or with a partner; or in patients having regular, unprotected intercourse and without any known etiology for either partner suggestive of impaired reproductive ability, evaluation should be initiated at 12 months when the female partner is under 35 years of age and at 6 months when the female partner is 35 years of age or older. Nothing in this definition shall be used to deny or delay treatment to any individual, regardless of relationship status or sexual orientation.” Please see below for medical necessity criteria for specific infertility related procedures.
Note: Requires Precertification:
Precertification of Cetrotide (cetrorelix acetate), ganirelix acetate, Follistim AQ (follitropin beta), Gonal-F (follitropin alfa), Menopur (menotropins), Novarel (chorionic gonadotropin), Pregnyl (chorionic gonadotropin), Ovidrel (choriogonadotropin alfa), and chorionic gonadotropin is required of all Aetna participating providers and members in applicable plan designs. For precertification, call (866) 782-2779 or fax (860) 754-2515. For Statement of Medical Necessity (SMN) precertification forms, see Specialty Pharmacy Precertification.
Note: Medical/Pharmacy Benefit Alignment of Coverage for Infertility Drugs and Procedures:
Medical necessity review of infertility drugs by Aetna Specialty Pharmacy Guideline Management may be bypassed for infertility ART drugs that are for use with infertility medical procedures if the infertility procedure has been approved for coverage under the member’s Aetna medical benefit plan. During precertification, a medical authorization number and confirmation of the approval of the infertility procedures will be required to bypass medical necessity review by Specialty Pharmacy Guideline Management. Note: Some plans may require medical necessity review of all infertility drugs by Aetna Specialty Guideline Management. Members of these plans must undergo Specialty Pharmacy Guideline Management medical necessity review of all infertility drugs regardless of whether the drugs are for use with approved infertility medical procedures.
Notes:
- For purposes of this entire policy, coverage is subject to the terms and conditions of the member's benefit plan. Coverage may vary due to state mandates and plan customization; please check plan documents.
- For plans with an Advanced Reproductive Technology (ART) benefit (please check benefit plan descriptions), less invasive therapeutic approaches should be attempted prior to undertaking more invasive procedures, as directed by an appropriate, licensed medical specialist. The medical necessity criteria in the Advanced Reproductive Technology section below are met for persons who are unable to conceive after an appropriate trial of egg-sperm contact. For women under 35 years of age, an appropriate trial of egg-sperm contact requires 12 months of regular intravaginal inseminations or 4 cycles of timed intrauterine or intracervical inseminations, documented in the medical record. For women 35 years of age and older, an appropriate trial of egg-sperm contact requires 6 months of regular intravaginal inseminations or 3 cycles of timed intrauterine or intracervical insemination, documented in the medical record. This requirement applies to all individuals regardless of sexual orientation or the availability of a reproductive partner. For IVF procedures under the ART benefit, these requirements for a trial of egg-sperm contact are waived for persons for whom intravaginal, intrauterine, or intracervical inseminations would not be expected to be effective and IVF procedures are the only effective treatment (see In Vitro Fertilization (IVF) Procedures subsection below.)
- Most plans exclude coverage of infertility services for persons who have had a previous sterilization procedure, including tubal sterilization and vasectomy, with or without surgical reversal, and for persons who have undergone a hysterectomy. Please check benefit plan descriptions for details. In addition, infertility services for persons who have undergone voluntary sterilization procedures are not covered because such services are the result of an elective procedure intended to prevent conception.
- Some plans exclude coverage of Advanced Reproductive Technology (ART) using a woman's own eggs for women with poor ovarian reserve. Ovarian reserve is determined by measurement of menstrual cycle day 3 serum follicle-stimulating hormone (FSH) drawn after the normal onset of menstruation, or after progesterone induced menstruation for women who do not reliably menstruate. For women 39 years of age and older, ovarian responsiveness is determined by measurement of day 3 FSH obtained within the prior 6 months. For women who are less than 40 years of age, the day 3 FSH must be less than 19 mIU/mL in their most recent laboratory test to use their own eggs. For women 40 years of age and older, their unmedicated day 3 FSH must be less than 19 mIU/mL in all prior tests to use their own eggs. Please check benefit plan descriptions.
- ART services for women 40 years of age and older with natural menopause is not covered because it is not considered medically necessary treatment of disease; natural menopause is not considered a disease. For women 40 years of age and older, their unmedicated day 3 FSH must be less than 19 mIU/mL in all prior tests to document that they are not menopausal and eligible for coverage of ART. Women who are less than 40 years of age who have a day 3 FSH greater than 19 mIU/L are considered to have the disease of premature ovarian failure (also known as premature ovarian insufficiency, primary ovarian insufficiency, or hypergonadotropic hypogonadism). For women with premature ovarian failure, ART (in vitro fertilization) services are considered medically necessary until they reach 45 years of age. Women 40 years of age and older with premature ovarian failure may submit a new unmedicated D3 FSH level to utilize her own oocytes (even if she has had an elevated D3 FSH level above 40 years of age in the past). For women 40 years of age and older with premature ovarian failure, the day 3 FSH must be less than 19 mIU/mL in their most recent laboratory test to use their own eggs. Please check benefit plan descriptions.
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Medical Necessity
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Females: Basic Infertility Services
The following services are considered medically necessary:
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History and Physical Examination
Basal body temperature;
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Laboratory Studies
- Anti-adrenal antibodies for apparently spontaneous primary ovarian insufficiency (premature ovarian failure);
- Anti-sperm antibodies (e.g., immunobead or mixed antiglobulin method);
- Chlamydia trachomatis screening (see CPB 0433 - Chlamydia Trachomatis - Screening and Diagnosis);
- Fasting and 2 hours post 75 gram glucose challenge levels;
- Lipid panel (total cholesterol, HDL cholesterol, triglycerides);
- Rubella serology;
- Testing for viral status (HIV, hepatitis B, hepatitis C);
- Serum hormone levels:
- Androgens (testosterone, androstenedione, dehydroepiandrosterone sulfate (DHEA-S) if there is evidence of hyperandrogenism (e.g., hirsuitism, acne, signs of virilization) or ovulatory dysfunction;
- Anti-mullerian hormone (AMH), for the following indications:
- assessing menopausal status, including premature ovarian failure;
- assessing ovarian status, including ovarian reserve and ovarian responsiveness, as part of an evaluation for infertility and assisted reproduction protocols such as in vitro fertilization;
- Gonadotropins (serum follicle-stimulating hormone [FSH], luteinizing hormone [LH]) for women with irregular menstrual cycles (see Appendix for medical necessity limitations) or age-related ovulatory dysfunction. Note: Aetna considers urinary FSH testing to be experimental, investigational, or unproven. Serum, not urinary, FSH is the standard of care for determination of menopausal status (AACE, 1999; NAMS, 2000; SOGC, 2002);
- Human chorionic gonadotrophin (hCG) (see Appendix for medical necessity limitations);
- Prolactin for women with an ovulatory disorder, galactorrhea, or a pituitary tumor;
- Progestins (progesterone, 17-hydroxyprogesterone) (see Appendix for medical necessity limitations);
- Estrogens (estradiol) (see Appendix for medical necessity limitations);
- Thyroid stimulating hormone (TSH) for women with symptoms of thyroid disease;
- Adrenocortitrophic hormone (ACTH) for ruling out Cushing's syndrome or Addison's disease in women who are amenorrheic;
- Clomiphene citrate challenge test;
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Karyotype testing for couples with recurrent pregnancy loss (2 or more consecutive spontaneous abortions) (see CPB 0348 - Recurrent Pregnancy Loss);
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Artificial Insemination(s) (intrauterine, intracervical, or intravaginal)
Note: Some Aetna benefit plans may exclude coverage of artificial insemination (AI). For Aetna benefit plans that cover artificial insemination, coverage may be limited to a maximum number of cycles per lifetime. Please check benefit plan descriptions.
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Diagnostic Procedures
The following diagnostic procedures are considered medically necessary:
- CT or MR imaging of sella turcica is considered medically necessary if prolactin is elevated;
- Endometrial biopsy;
- Hysterosalpingography (hysterosalpingogram [HSG]) or hysterosalpingo-contrast-ultrasonography (HyCoSy) to screen for tubal occlusion;
The following are considered experimental, investigational, or unproven to screen for tubal occlusion (not an all-inclusive list) because of a lack of reliable evidence of effectiveness:
- Sonohysterosalpingography or saline hysterosalpingography (e.g., Femvue);
- Hysterosalpingo-foam sonography (HyFoSy) (e.g. ExEm Foam);
- Hysteroscopy, salpingoscopy (falloscopy), hydrotubation where clinically indicated;
- Laparoscopy and chromotubation (contrast dye) to assess tubal and other pelvic pathology, and to follow-up on hysterosalpingography abnormalities;
- Sonohysterography to evaluate the uterus;
- Ultrasound (e.g., ovarian, transvaginal, pelvic) (see Appendix for medical necessity limitations);
- Monitoring of ovarian response to ovulatory stimulants:
- Estradiol (see Appendix for medical necessity limitations);
- FSH (see Appendix for medical necessity limitations);
- hCG quantitative (see Appendix for medical necessity limitations);
- LH assay (see Appendix for medical necessity limitations);
- Progesterone (see Appendix for medical necessity limitations);
- Serial ovarian ultrasounds are considered medically necessary for cycle monitoring (see Appendix for medical necessity limitations);
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Non-Surgical Treatments
The following non-surgical treatments are considered medically necessary:
- Aromatase inhibitors (e.g., anastrozole [Arimidex], exemestane [Aromasin], and letrozole [Femara]);
- Corticosteroids (e.g., dexamethasone, prednisone);
- Estrogens (e.g., estrone and conjugated estrogens [Premarin]);
- Hepatitis B vaccination of partners of people with hepatitis B;
- Lutropin alfa (Luveris) for use in combination with human FSH to stimulate follicular development in infertile hypo-gonadotropic hypo-gonadal women or in women with a profound LH deficiency defined as LH less than 1.2 International Units/L;
- Metformin (Glucophage) for women with WHO Group II anovulatory disorders such as polycystic ovarian syndrome;
- Progestins (oral, topical gel (8 % progesterone) (Crinone 8 %, Prochieve 8 %) or intramuscular progestins and progesterone vaginal suppositories (Endometrin), see CPB 0510 - Progestins);
- Prolactin inhibitors (bromocriptine (Parlodel), cabergoline (Dostinex), peroglide (Permax)) for women with ovulatory disorders due to hyperprolactinemia;
- Rubella vaccination of women susceptible to rubella;
- Tamoxifen (Novaldex) or oral clomiphene citrate (Clomid, Serophene) for ovulation induction;
Note: The medications listed above may not be covered for members without pharmacy benefit plans; in addition, some pharmacy benefit plans may exclude or limit coverage of some or all of these medications. Please check benefit plan descriptions for details.
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Infertility Surgery
The following are considered medically necessary:
- Hysteroscopic adhesiolysis for women with amenorrhea who are found to have intrauterine adhesions;
- Hysteroscopic or fluoroscopic tubal cannulation (salpingostomy, fimbrioplasty), selective salpingography plus tubal catheterization, or transcervical balloon tuboplasty for women with proximal tubal obstruction (see CPB 0347 - Transcervical Balloon Tuboplasty);
- Laparoscopic cystectomy for women with ovarian endometriomas;
- Laparoscopy for treatment of pelvic pathology;
- Open or laparoscopic resection, vaporization, or fulguration of endometriosis implants plus adhesiolysis in women with endometriosis;
- Ovarian wedge resection or ovarian drilling for women with WHO Group II ovulation disorders such as polycystic ovarian syndrome who have not responded to clomiphene citrate;
- Removal of myomas, uterine septa, cysts, ovarian tumors, and polyps;
- Surgical tubal reconstruction (unilateral or bilateral tubal microsurgery, laparoscopic tubal surgery, tuboplasty and tubal anastomosis) for women with mid or distal tubal occlusion and for women with proximal tubal disease where tubal cannulation has failed or where severe proximal tubal disease precludes the likelihood of successful cannulation;
- Tubal ligation (salpingectomy) for women with hydrosalpinges who are contemplating in vitro fertilization, as this has been demonstrated to improve the chance of a live birth before in-vitro fertilization treatment;
- Cervicectomy/trachelectomy is an acceptable alternative to hysterectomy for treatment of early stage (IA2 or small IB1) cervical adenocarcinoma in women who wish to preserve their fertility.
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Male Infertility
The following services are considered medically necessary:
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History and Physical Examination
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Laboratory Studies
- Anti-sperm antibodies (e.g., immunobead or mixed antiglobulin method);
- Cultures:
- Prostatic secretion;
- Semen;
- Urine;
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Serum hormone levels:
- Androgens (testosterone, free testosterone) - if initial testosterone level is low, a repeat measurement of total and free testosterone as well as serum luteinizing hormone (LH) and prolactin levels is medically necessary;
- Gonadotropins (FSH, LH);
- Prolactin for men with reduced sperm counts, galactorrhea, or pituitary tumors;
- Sex hormone binding globulin (SHGB) for men with signs and symptoms of hypogonadism and low normal testosterone levels. (SHGB is not indicated in the routine evaluation of male infertility);
- Thyroid stimulating hormone (TSH) for men with symptoms of thyroid disease;
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Semen analysis - Semen analysis (volume, pH, liquefaction time, sperm concentration, total sperm number, motility (forward progression), motile sperm per ejaculate, vitality, round cell differentiation (white cells versus germinal), morphology, viscosity, agglutination) is considered medically necessary for the evaluation of infertility in men. Because of the marked inherent variability of semen analyses, an abnormal result should be confirmed by at least one additional sample collected one or more weeks after the first sample;
- For men with abnormal semen analysis exposed to gonadotoxins, up to 4 semen analyses are considered medically necessary;
- For men with a normal initial semen analysis, a repeat semen analysis is considered medically necessary if there is no pregnancy 4 months after the initial normal semen analysis;
- If the result of the first semen analysis is abnormal and the man has not been exposed to gonadotoxins, up to 2 repeat confirmatory tests may be considered medically necessary;
- Semen leukocyte analysis (e.g., Endtz test, immunohistochemical staining);
- Seminal fructose; Note: Seminal alpha-glucosidase, zinc, citric acid, and acid phosphatase are considered experimental, investigational, or unproven.
- Blood test for cytogenetic analysis (karyotype and FISH) in men with severe deficits of semen quality or azoospermia (for consideration of intracytoplasmic sperm injection [ICSI]);
- Y chromosome microdeletion analysis in men with severe deficits of semen quality or azoospermia (for consideration of intracytoplasmic sperm injection [ICSI]); Note: Y chromosome microdeletion analysis is not routinely indicated before ICSI, and is subject to medical necessity review.
- Sperm penetration assay (zona-free hamster egg penetration test);
- Karyotyping for persons with recurrent pregnancy loss (defined as 2 or more consecutive spontaneous abortions) (See CPB 0348 - Recurrent Pregnancy Loss) and for men with severe deficits in semen quality or nonobstructive azoospermia (for consideration of intracytoplasmic sperm injection [ICSI]);
- Testing for viral status (HIV, hepatitis B, hepatitis C);
- Genetic testing of CFTR mutations for a man and his female partner if the man has congenital absence of the vas deferens (CAVD);
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Diagnostic procedures
- CT or MR imaging of sella turcica if prolactin is elevated;
- Scrotal exploration;
- Scrotal (testicular) ultrasound (See CPB 0532 - Scrotal Ultrasonography);
- Testicular biopsy;
- Transrectal ultrasound (See CPB 0001 - Transrectal Ultrasound);
- Vasography;
- Venography;
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Treatments
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Endocrine Management
- Anti-estrogens (tamoxifen (Nolvadex)) for men with elevated estrogen levels;
- Clomiphene (Clomid, Serophene);
- Corticosteroids (e.g., dexamethasone, prednisone);
- Prolactin inhibitors (bromocriptine (Parlodel), cabergoline (Dostinex)) for persons with hyperprolactinemia;
- Thyroid hormone replacement for men with thyroid deficiency;
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Injectable Endocrine Management
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Gonadotropin releasing hormone analogs and antagonists
For gonadotropin-releasing hormone analogs and antagonists (GnRH; luteinizing hormone releasing hormone (LHRH)) see CPB 0501 - Gonadotropin-Releasing Hormone Analogs and Antagonists;
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Gonadotropins
For human chorionic gonadotropin (hCG) (e.g., Novarel, Ovidrel, Pregnyl, generic formulation), see CPB 1081 - Human Chorionic Gonadotropin (hCG).
For follitropins (e.g., follitropin alfa [Gonal-f]; follitropin beta [Follistim AQ]), see CPB 1082 - Follitropins and Menotropins.
Note: Many plans that otherwise cover infertility treatments exclude coverage for infertility injectable medications. Please check benefit plan descriptions.
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- Antibiotics for men with an identified infection; Note: Intra-prostatic antibiotic injection is considered experimental, investigational, or unproven;
- Varicocelectomy (spermatic vein ligation) - see CPB 0413 - Varicocele: Selected Treatments;
- Spermatocelectomy and hydrocelectomy;
- Surgical repair of vas deferens: vasovasostomy; Note: Most plans exclude coverage for reversal of sterilization procedures. This would include vasectomy. Please check benefit plan descriptions for details.
- Surgical correction of epididymal blockage for men with obstructive azoospermia:
- Epididymectomy;
- Epididymovasostomy;
- Excision of epididymal tumors and cysts;
- Epididymostomy;
- Transurethral resection of ejaculatory ducts (TURED) for obstruction of ejaculatory ducts;
- Orchiopexy;
- Alpha sympathomimetic agents for retrograde ejaculation (e.g., phenylephrine, imipramine);
- Hepatitis B vaccination of partners of people with hepatitis B;
- Impotence treatments - see CPB 0007 - Erectile Dysfunction.
Note: Under most Aetna benefit plans, self-administered prescription medications are covered under the pharmacy benefit. Please check benefit plan descriptions.
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Electroejaculation
Aetna considers electroejaculation medically necessary DME to overcome total anejaculation secondary to neurologic impairment, which most commonly occurs among members with the following conditions:
- Diabetic neuropathy;
- Prior retroperitoneal surgery (most commonly retroperitoneal lymphadenectomy as a treatment of testicular cancer);
- Spinal cord injury.
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Donor Insemination
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Donor insemination is considered medically necessary for the following indications:
- Non-obstructive azoospermia;
- Obstructive azoospermia;
- Severe deficits in semen quality in couples who do not wish to undergo intracytoplasmic sperm injection (ICSI);
- Severe rhesus isoimmunization;
- Where there is a high risk of transmitting a genetic disorder in the male partner to the offspring;
- Where there is a high risk of transmitting an infectious disease (such as HIV) to the partner or offspring.
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Advanced Reproductive Technology
Note: Coverage is limited to plans with an ART benefit; please check benefit plan descriptions.
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Injectable Medications
See CPB 0020 - Injectable Medications.
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Gonadotropin releasing hormone analogs and antagonists
For gonadotropin-releasing hormone analogs and antagoinists (GnRH; luteinizing hormone releasing hormone [LHRH]) (e.g., generic leuprolide acetate injection, leuprolide acetate for depot suspension [Lupron Depot], goserelin [Zoladex], histrelin [Supprelin LA], triptorelin [Trelstar; Triptodur], ganirelix acetate/cetrorelix acetate [Cetrotide]), see CPB 0501 - Gonadotropin-Releasing Hormone Analogs and Antagonists;
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Gonadotropins:
For human chorionic gonadotropin (hCG) (e.g., Novarel, Ovidrel, Pregnyl, generic formulation), see CPB 1081 - Human Chorionic Gonadotropin (hCG).
For follitropins (e.g., follitropin alfa [Gonal-f]; follitropin beta [Follistim AQ]), see CPB 1082 - Follitropins and Menotropins.
For menotropins for injection (Menopur), see CPB 1082 - Follitropins and Menotropins.
Note: Many plans exclude coverage for infertility injectable medications; other plans may limit coverage of ovulation induction cycles with menotropins to a maximum number per lifetime. Please check plan documents for details.
Note: Under most Aetna benefit plans, self-administered prescription medications are covered under the pharmacy benefit. Please check benefit plan descriptions.
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Ovulation Induction
Aetna considers oral or injectable ovulation induction (OI) medically necessary for women 37 years of age or younger who are unable to conceive or produce conception after an appropriate trial of egg-sperm contact. Oral ovulation induction may occur concurrently with the cycles of egg-sperm contact required to establish medical necessity for ART. For women under 35 years of age, an appropriate trial of egg-sperm contact requires 12 months of regular intravaginal inseminations or 4 cycles of timed intrauterine or intracervical inseminations documented in the medical record. For women 35 years of age and older, an appropriate trial of egg-sperm contact requires 6 months of regular intravaginal inseminations or 3 cycles of timed intrauterine or intracervical insemination documented in the medical record.
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In Vitro Fertilization (IVF) procedures
Aetna considers the following in vitro fertilization (IVF) procedures medically necessary for persons who meet any of the following criteria:
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Women who have failed to conceive after a trial of ovulation induction:
- For women 37 years of age or younger, three cycles of oral or injectable ovulation induction (with or without intravaginal, intrauterine, or intracervical inseminations); or
- For women 38 years of age or older, no trial of ovulation induction is required; or
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Persons for whom intravaginal, intrauterine, or intracervical inseminations would not be expected to be effective and IVF would be expected to be the only effective treatment, including:
- Men with azoospermia or severe deficits in semen quality or quantity (see Appendix); or
- Women with tubal factor infertility:
- Bilateral tubal disease (e.g., salpingitis isthmica nodosum, tubal obstruction, absence, or hydrosalpinges).
- Endometriosis stage 3 or 4 (see Appendix).
- Failure to conceive after pelvic surgery with restoration of normal pelvic anatomy (e.g., myomectomy of cavitary-obscuring myomata, resection of intrauterine adhesions or uterine septum, or surgical reconstruction of tubal disease):
- After regular egg-sperm contact for 6 months if less than 40 years of age;
- After regular egg-sperm contact for 3 months if 40 years of age or older.
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Unilateral hydrosalpinx with failure to conceive:
- After regular egg-sperm contact for 12 months if less than 40 years of age;
- After regular egg-sperm contact for 6 months if 40 years of age or older.
- Inadvertent ovarian hyperstimulation (estradiol level was greater than 1,000 pg/ml plus greater than 3 follicles greater than 16 mm or 4 to 8 follicles greater than 14 mm or a larger number of smaller follicles) during preparation for a planned stimulated cycle in women less than 38 years of age.
- Women who have had a hysterectomy, or who have a medical contraindication to pregnancy such as severe cardiac disease, or have a medical condition that requires the mother to ingest a fetotoxic agent. Note: Some plans limit and/or exclude coverage for gestational surrogacy; please check benefit plan descriptions.
Note on coverage of advanced reproduction technology (ART) for preimplantation genetic testing for monogenic disorders (PGT-M) (formerly called preimplantation genetic diagnosis [PGD])embryo biopsy, and testing of the biopsied material, is covered for persons with an ART benefit when medical necessity criteria for PGT-M are met as set forth in CPB 0358 - Invasive Prenatal Diagnosis of Genetic Diseases.
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IVF with embryo transfer is considered medically necessary when criteria for ART are met. IVF with embryo transfer includes:
- Embryo transfer (transcervical transfer back to the donor) (including cryopreserved embryo transfer);
- Frozen embryo transfer (FET); (Note: It may be considered medically necessary to freeze embryos not transferred during a stimulated IVF treatment cycle, and to transfer the embryos before the next stimulated treatment cycle because this will minimize ovulation induction and egg collection, both of which carry risks for the woman and use more resources. Before proceeding to a fresh ART cycle, previously frozen oocytes must be used (i.e. fertilized and transferred). Similarly, Before proceeding to the next fresh ART cycle, FET using cryopreserved embryos must be used if there are reasonable quality (grade B or its equivalent) cryopreserved embryo(s) available.
- Oocyte (egg) insemination in laboratory dish;
- Oocyte (egg) retrieval via laparoscope or transvaginal needle aspiration of follicles;
- Sperm preparation and capacitation;
- Intracytoplasmic sperm injection (ICSI) is considered medically necessary for the following:
- Severe deficits in semen quality or quantity, including azoospermia or oligospermia (obstructive or non-obstructive) (see Appendix on Semen Quality and Quantity);
- To fertilize frozen oocytes for in vitro fertilization;
- For persons facing iatrogenic infertility due to chemotherapy, pelvic radiotherapy, other gonadotoxic therapies, or ovary or testicle removal for treatment of disease; or
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For couples where a previous IVF treatment cycle has resulted in failed or poor fertilization (IVF cycles that resulted in less than 50% fertilization).
Notes:Intracytoplasmic sperm injection (ICSI) is considered not medically necessary in men whose abnormal sperm quality or quantity had been rectified by varicocelectomy. For use of ICSI in preimplantation genetic testing for monogenic disorders (PGT-M) (formerly called preimplantation genetic diagnosis [PGD]) and preimplantation genetic testing for aneuploidy (PGT-A) (formerly called preimplantation genetic screening [PGS]), see CPB 0358 - Invasive Prenatal Diagnosis of Genetic Diseases.
Physiological, hyaluronan-selected intracytoplasmic sperm injection (PICSI) is a variation of intracytoplasmic sperm injection (ICSI) that uses hyaluronic acid (HA) to select sperm. The PICSI method is considered experimental, investigational, or unproven because of a lack of reliable evidence of effectiveness compared to standard ICSI.
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Assisted hatching is considered medically necessary when the plan in the cycle is to transfer the embryos into the uterus and the member meets any of the following criteria:
- Age of embryo recipient is 38 years or older; or
- Multiple (2 or more) failed embryo transfer attempts; or
- Thickened zona pellucida.
Note: Assisted hatching is a process to assist in the implantation of the embryo; unless the cycle involves that transfer of the embryo assisted hatching is considered not medically necessary.
Note on IVF cycles for embryo bankingIVF cycles for the sole purpose of embryo banking (where none of the embryos that are suitable for transfer are used in the current cycle in which they are created, but are frozen for use in a future cycle) is not considered treatment of disease and is not covered.
Note on oocytes used in ART cyclesIVF cycles using either fresh or previously frozen oocytes are considered medically necessary when the ART cycle is considered medically necessary.
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Other Advanced Reproductive Technology (ART) Procedures
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Gamete intra-fallopian transfer (GIFT) is considered medically necessary as an alternative to IVF for women with female factor infertility. GIFT includes:
- Immediate loading of the eggs into a transfer catheter with sperm and insertion into the member’s fallopian tube via the same laparoscope (the member must have at least 1 patent fallopian tube for this method to be an effective treatment for infertility)
- Oocyte (egg) retrieval via laparoscope.
GIFT is considered experimental, investigational, or unproven for person with male factor infertility or unexplained infertility problems because there is insufficient evidence to recommend GIFT over IVF for these indications.
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Zygote intra-fallopian transfer (ZIFT), tubal embryo transfer (TET), pronuclear stage tubal embryo transfer (PROUST) is considered medically necessary as an alternative to IVF for women with female factor infertility.
ZIFT is considered experimental, investigational, or unproven for persons with male factor infertility or unexplained infertility problems because there is insufficient evidence to recommend ZIFT over IVF for these indications.
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Specialized sperm retrieval techniques (including vasal sperm aspiration, microsurgical epididymal sperm aspiration (MESA), percutaneous epididymal sperm aspiration (PESA), electroejaculation, testicular sperm aspiration (TESA), microsurgical testicular sperm extraction (TESE), seminal vesicle sperm aspiration, and sperm recovery from bladder or urine for retrograde ejaculation) is considered medically necessary to overcome anejaculation or azoospermia that is not due to a previous elective sterilization. (see Appendix on Semen Quality and Quantity)
Note: Most plans exclude coverage of infertility services for persons who have undergone sterilization. This would include sperm retrieval for men who have undergone vasectomy. Please check benefit plan descriptions for details.
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Oocyte donation is considered medically necessary for managing infertility problems associated with the following conditions, when the infertile member is the intended recipient of the resulting embryos:
- Bilateral oophorectomy;
- Gonadal dysgenesis including Turner syndrome;
- High-risk of transmitting a genetic disorder from the female partner to the offspring;
- IVF treatment failure
- Ovarian failure following chemotherapy or radiotherapy; or
- Premature ovarian failure (failure of ovulation in woman younger than 40 years of age) (considered medically necessary until the woman with POF is 45 years of age).
Note: Many Aetna plans that otherwise cover ART exclude coverage of fees associated with oocyte donation, including recruitment and selection of donors, ovarian stimulation of donors, collection of oocytes from donors, and screening and storage of donor oocytes. Please check benefit plan descriptions for details. Under plans with benefits for ART that have this exclusion, medically necessary ART services are covered only once an embryo is created from the donor egg.
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Retrieval, freezing, and/or storage of oocytes (eggs) or sperm; and creation, freezing, and storage of embryos is considered medically necessary for use in persons facing iatrogenic infertility due to chemotherapy, pelvic radiotherapy, other gonadotoxic therapies, or ovary or testicle removal for treatment of disease.
Retrieval, freezing, and/or storage of oocytes (eggs) or sperm; and creation, freezing, and storage of embryos to circumvent reproductive aging in healthy persons is considered experimental, investigational, or unproven because of insufficient evidence in the peer-reviewed literature.
Note: Some Aetna plans have a specific contractual exclusion of coverage of any charges associated with embryo cryopreservation or storage of cryopreserved embryos. Please check benefit plan descriptions. In addition, cryopreservation of embryos and gametes (other than short-term cryopreservation of embryos that are necessary for contemporaneous use in infertile persons currently under active fertility treatment, or use of cryopreserved embryos or mature gametes in persons facing infertility due to chemotherapy or other gonadotoxic therapies or gonad removal) is not considered treatment of disease and is not covered.
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Sperm cryopreservation to circumvent reproductive aging in healthy men is considered experimental, investigational, or unproven.
Note: Some Aetna plans have a specific contractual exclusion of coverage of any charges associated with sperm cryopreservation or storage. Please check benefit plan descriptions. In addition, cryopreservation of sperm (other than cryopreserved sperm in men facing infertility due to chemotherapy or other gonadotoxic therapies or gonad removal) is not considered treatment of disease and is not covered.
Note: A cycle of ART defined in the CPB may be any of the following: IVF (with fresh embryos), IVF/frozen embryo transfer, GIFT or ZIFT.
Note on elective single embryo transfer: In order to reduce the number of high-order multiple pregnancies, the American Society for Reproductive Medicine (ASRM, 2021) recommends elective single embryo transfer (eSET) for women under 35 years of age, or for transfer of a euploid embryo regardless of member age. For women who meet these criteria and undergo transfer of a single fresh embryo that does not result in a pregnancy (defined as absence of a documented fetal heartbeat), and who are enrolled in a benefit plan that limits the number of covered IVF cycles, Aetna will consider the transfer of one cryopreserved embryo immediately following the unsuccessful fresh embryo transfer as part of the same IVF cycle. Please check benefit plan description for details.
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Experimental, Investigational, or Unproven
The following are considered experimental, investigational, or unproven for infertility (not an all-inclusive list):
- Acupuncture (see CPB 0135 - Acupuncture)
- Bariatric surgery (see CPB 0157 - Obesity Surgery);
- Dehydroepiandrosterone (DHEA)
- Direct intra-peritoneal insemination, fallopian tube sperm transfusion, intra-follicular insemination, and the use of sperm precursors (i.e., round or elongated spermatid nuclei, immature sperm)
- Drainage of ovarian cyst
- DuoStim IVF protocol
- Early Embryo Viability Assessment (Eeva) test
- EmbryoGlue
- Evaluation of CYP1A1 rs4646903 T > C genetic variations for risk of male infertility
- Evaluation of FAS/FASL genetic variations for risk of male infertility
- Evaluation of telomere length
- Fine needle aspiration ("mapping") of testes
- FSH manipulation of women with elevated FSH levels (an elevated FSH level is a marker of reduced ovarian reserve, as occurs with advancing age. Elevated FSH-related (i.e., age-related) infertility has not been proven to be affected by interventions to reduce FSH levels)
- Germ cell transplantation or cultured testicular stem cells
- Growth hormone: there is inadequate evidence that the use of adjuvant growth hormone treatment during ovulation induction improves pregnancy rates. See CPB 0170 - Growth Hormone (GH) and Growth Hormone Antagonists.
- GIFT for person with male factor infertility or unexplained infertility problems
- Hyperbaric oxygen therapy for the treatment of male infertility
- Intralipid infusion for the treatment of female infertility
- Intrauterine injection/infusion of platelet rich plasma for the treatment of female infertility
- Intravenous immunoglobulins for treatment of infertility (see CPB 0348 - Recurrent Pregnancy Loss and CPB 0206 - Parenteral Immunoglobulins)
- In-vitro maturation of oocytes
- Leokocyte immunization (immunizing the female partner with the male partner's leukocytes (see CPB 0348 - Recurrent Pregnancy Loss)
- Microdissection of the zona
- Parenteral administration of lipids
- Partial zonal dissection (PZD)
- Post-coital test (PCT) (Simms-Huhner test) of cervical mucus
- Preimplantation genetic testing for aneuploidy (PGT-A) (formerly called preimplantation genetic screening (PGS)) for IVF optimization (see CPB 0358 - Invasive Prenatal Diagnosis of Genetic Diseases)
- Stem cell therapy
- Subzonal sperm insertion (SUZI)
- Uterine transplant
- Vaginal sildenafil
- Vasodilators for women undergoing fertility treatment
- ZIFT for persons with male factor infertility or unexplained infertility problems
- The following sperm function tests are considered experimental, investigational, or unproven:
- Acrosome reaction test
- Cap-Score Test
- Comet assay
- Computer-assisted sperm analysis (CASA)/computer-assisted sperm motion analysis
- Hemizona assay
- Hyaluronan binding assay
- Hypoosmotic swelling test
- In vitro testing of sperm penetration
- Reactive oxygen species (ROS) test
- Sperm chromatin assay
- Spern DNA condensation test
- Sperm DNA fragmentation assay
- Sperm nucleus maturation
- TUNEL assay
- For follitropins and menotropins, see CPB 1082 - Follitropins and Menotropins
- For human chorionic gonadotropin (hCG), see CPB 1081 - Human Chorionic Gonadotropin (hCG)
- The following laboratory studies are considered experimental, investigational, or unproven for infertility:
- Analysis of Infectious Chronic Endometritis (ALICE) (Igenomix)
- Anti-CarP (anti-carbamylated proteins) panel
- Antinuclear antibodies
- Antiovarian antibodies
- Antiphospholipid antibodies
- Antiphosphatidic acid antibodies
- Antiphosphatidylethanolamine antibodies
- Antiphosphatidylglycerol antibodies
- Antiphosphatidylinositol antibodies
- Antiphosphatidylserine antibodies
- Antiprothrombin antibodies (see CPB 0662 - Antiprothrombin Antibody Testing)
- Antithrombin III (ATIII) activity
- Antithrombin III (ATIII) antigen
- Antithyroglobulin antibodies
- Embryotoxicity assay (see CPB 0348 - Recurrent Pregnancy Loss)
- Endometrial Microbiome Metagenomic Analysis (EMMA) (Igenomix)
- Endometrial receptivity testing (e.g., endometrial receptivity analysis (Igenomix), endometrial receptivity array (ERA), integrin testing, beta-3 integrin test)
- Evaluation of telomere length
- Factor V Leiden coagulation
- Factor V Leiden mutation (see CPB 0140 - Genetic Testing)
- HLA genotyping (A, B, C, DR, DQ)
- Homocysteine (see CPB 0763 - Homocysteine Testing)
- Methylenetetrahydrofolate reductase (MTHFR)
- Oxidative Stress Adduct Test (OSA)
- Plasminogen Activator Inhibitor-I activity
- Plasminogen Activator Inhibitor-I (PAI-1) antigen
- Protein C activity
- Protein C antigen
- Protein S activity
- Protein S antigen (free or total)
- Prothrombin (Factor II) mutation (see CPB 0140 - Genetic Testing)
- Uterine and endometrial receptivity testing (Endometrial function test (EFT) (cyclin E and p27) and E-tegrity)
- Measurement of natural killer (NK) cell activity
- Reproductive immunophenotyping
- Serum inhibin B measurement (value in assessing ovarian reserve is uncertain)
- Th1 (T Helper 1) and Th2 (T Helper 2) intracellular cytokine assay (Th1/Th2 ratio)
- uBiome SmartJane screen (see CPB 0650 - Polymerase Chain Reaction Testing: Selected Indications)
- Vaginal microbiota.
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Related Policies
- CPB 0001 - Transrectal Ultrasound
- CPB 0007 - Erectile Dysfunction
- CPB 0020 - Injectable Medications
- CPB 0135 - Acupuncture
- CPB 0140 - Genetic Testing
- CPB 0157 - Obesity Surgery
- CPB 0170 - Growth Hormone (GH) and Growth Hormone Antagonists
- CPB 0189 - Genetic Counseling
- CPB 0206 - Parenteral Immunoglobulins
- CPB 0323 - Preconceptional Sex Selection Techniques
- CPB 0347 - Transcervical Balloon Tuboplasty
- CPB 0348 - Recurrent Pregnancy Loss
- CPB 0358 - Invasive Prenatal Diagnosis of Genetic Diseases
- CPB 0413 - Varicocele: Selected Treatments
- CPB 0433 - Herpes Simplex Virus - Screening and Diagnosis
- CPB 0501 - Gonadotropin-Releasing Hormone Analogs and Antagonists
- CPB 0510 - Progestins
- CPB 0532 - Scrotal Ultrasonography
- CPB 0650 - Polymerase Chain Reaction Testing: Selected Indications
- CPB 0662 - Antiprothrombin Antibody Testing
- CPB 0763 - Homocysteine Testing
- CPB 1081 - Human Chorionic Gonadotropin (hCG)
- CPB 1082 - Follitropins and Menotropins
Background
The American Society for Reproductive Medicine (ASRM, 2023) defines infertility as a disease, condition, or status in which an individual is unable to achieve a successful pregnancy based on medical, sexual, and reproductive history, age, physical examination findings, diagnostic testing, or a combination of these factors, or when medical intervention, including but not limited to the use of donor gametes or donor embryos, is required to achieve pregnancy, either individually or with a partner. In individuals engaging in regular, unprotected intercourse without an identified cause of impaired reproductive ability, clinical evaluation is recommended after 12 months for those with a female partner under 35 years of age and after 6 months for those with a female partner aged 35 years or older. ASRM further states that this definition should not be used to deny or delay evaluation or treatment for any individual, irrespective of relationship status or sexual orientation.
Infertility is commonly categorized into several types based on reproductive history and underlying cause. Primary infertility refers to the inability to achieve a pregnancy in an individual or couple who has never previously conceived, while secondary infertility refers to difficulty achieving a subsequent pregnancy following at least one prior conception. Infertility may also be classified etiologically as female factor infertility, male factor infertility, or combined male and female factor infertility, reflecting the contribution of one or both partners to impaired reproductive potential. In a substantial subset of couples, no specific abnormality is identified despite standard evaluation, a condition termed unexplained infertility, which accounts for up to approximately 30% of cases.
Diagnostic investigation of infertility includes complete physical examinations and diagnostic testing for both partners. Infertility treatment may involve a series of medical and procedural interventions aimed at correcting the underlying cause.
Recurrent pregnancy loss is distinct from infertility and is defined as two or more pregnancy losses. For purposes of determining when evaluation and treatment for infertility or recurrent pregnancy loss are appropriate, pregnancy is defined as a clinical pregnancy documented by ultrasonography or histopathologic examination (ASRM, 2012).
Female basic infertility services encompass a comprehensive, evidence‑based approach to evaluating and managing infertility, consistent with guidance from the American Society for Reproductive Medicine (ASRM). Initial assessment includes a detailed history and physical examination, along with targeted laboratory testing to evaluate ovulatory function, ovarian reserve, endocrine disorders, infectious status, and immune or genetic factors when clinically indicated. Core hormonal testing may include serum FSH, LH, estradiol, progesterone, prolactin, TSH, and anti‑Müllerian hormone (AMH), while additional tests (e.g., androgens, ACTH, karyotype analysis) are reserved for specific clinical scenarios. ASRM emphasizes that infertility evaluation should be systematic, timely, and based on clinical findings rather than indiscriminate testing, with serum‑based assays preferred over urinary testing for hormonal assessment. Diagnostic procedures commonly used include pelvic and transvaginal ultrasound, hysterosalpingography to assess tubal patency, endometrial biopsy when indicated, and selective use of advanced imaging or laparoscopy to further evaluate uterine, tubal, or pelvic pathology (ASRM, 2020; ASRM, 2021).
Management of female infertility integrates non‑surgical, medical, and surgical interventions tailored to the underlying etiology. Medical treatments include ovulation induction with agents such as clomiphene citrate or aromatase inhibitors, metabolic and endocrine therapies (e.g., metformin for WHO Group II anovulation, prolactin inhibitors for hyperprolactinemia), hormonal support with progestins or estrogens when indicated, and adjunctive therapies addressing comorbid conditions. Assisted reproductive procedures such as artificial insemination may be incorporated depending on diagnosis and benefit design. Surgical interventions, ranging from hysteroscopic correction of intrauterine pathology to laparoscopic treatment of endometriosis or tubal disease, are directed at restoring normal reproductive anatomy or improving outcomes of assisted reproduction, including salpingectomy for hydrosalpinges prior to in vitro fertilization. ASRM recognizes these diagnostic and therapeutic modalities as integral components of infertility care when applied based on clinical indication, best available evidence, and individualized patient factors (ASRM, 2020; ASRM, 2021).
Male infertility services involve a structured, evidence‑based evaluation and management approach that addresses potential endocrine, genetic, infectious, anatomic, and functional contributors to impaired male reproductive potential, consistent with American Society for Reproductive Medicine (ASRM) guidance. Evaluation begins with a focused history and physical examination, followed by semen analysis as the cornerstone diagnostic test, with repeat testing recommended due to inherent variability. Additional laboratory studies may include targeted hormonal evaluation (e.g., testosterone, FSH, LH, prolactin, TSH) when semen parameters are abnormal or clinical features suggest endocrine dysfunction, as well as selective infectious, immunologic, or metabolic testing when indicated. Genetic testing, including karyotype analysis, Y‑chromosome microdeletion analysis, and CFTR mutation testing, is reserved for men with severe sperm abnormalities, azoospermia, or congenital absence of the vas deferens, particularly when assisted reproductive techniques such as intracytoplasmic sperm injection are being considered. Diagnostic imaging and procedures, including scrotal or transrectal ultrasound, pituitary imaging for hyperprolactinemia, and testicular biopsy, are used selectively to further characterize obstructive or non‑obstructive causes of infertility (ASRM, 2020; AUA/ASRM, 2021).
Management of male infertility is similarly etiology‑driven and may include medical, surgical, or supportive interventions. Medical therapies address reversible endocrine abnormalities (e.g., hypogonadism, hyperprolactinemia, thyroid disease), infection, or ejaculatory disorders, while injectable gonadotropin therapy may be used in select men with hypogonadotropic hypogonadism. Surgical interventions target correctable anatomic causes, such as varicocele repair, reconstruction of the reproductive tract for obstructive azoospermia, or correction of ejaculatory duct obstruction. Adjunctive techniques, including electroejaculation, may be used to obtain sperm in men with neurologic impairment resulting in anejaculation. ASRM emphasizes that male partner evaluation should occur in parallel with female evaluation, using targeted testing to avoid unnecessary interventions, and that management decisions should be individualized based on identified pathology, fertility goals, and overall treatment context (ASRM, 2020; AUA/ASRM, 2021).
Donor insemination is an established reproductive option used to achieve pregnancy when the use of a male partner’s sperm is contraindicated or not feasible, and its clinical application is supported by guidance from the American Society for Reproductive Medicine (ASRM). In medical practice, donor insemination may be utilized in cases of non‑obstructive or obstructive azoospermia, or in the setting of severe abnormalities in semen quality when couples choose not to pursue intracytoplasmic sperm injection (ICSI). It may also be indicated to mitigate maternal–fetal risk, such as in severe rhesus isoimmunization, or to avoid transmission of serious genetic conditions or infectious diseases, including HIV, from the male partner to the partner or offspring (ASRM, 2013; ASRM, 2021).
ASRM emphasizes that donor insemination involves careful consideration of medical, genetic, and infectious risk factors, as well as appropriate screening of donors to reduce the risk of disease transmission and adverse reproductive outcomes. The use of donor sperm is integrated within comprehensive infertility care and may be performed via intrauterine or intracervical insemination, depending on clinical circumstances. Selection of donor insemination as a reproductive strategy is guided by the underlying etiology of infertility, reproductive goals, and informed patient decision‑making, and is recognized as a clinically appropriate option within evidence‑based infertility management frameworks (ASRM, 2013; ASRM, 2021).
Male Infertility and Sperm Function
Guercini et al. (2005) reported that in chronic prostatitis there are many causes that may provoke a therapeutical failure of a systemic antibiotic treatment. At the moment a consensus has not been reached on the effectiveness of the many therapeutical options that are available with not one of these approaches being effective in all patients. In the authors' view the main causes of treatment failure are the well-known hurdle to antibiotic diffusion inside the glandular parenchyma associated with the so-called intra-prostatic bacterial biofilms and the possible presence of local auto-immune reactions. Given this background, these researchers tested ultrasound-guided intra-prostate infiltration of a cocktail of antibiotics and betamethasone, for therapeutical options. A total of 320 patients, referred for treatment because of symptoms indicative of chronic prostatitis, were enrolled in this study. The inclusion criteria were the severity of the symptoms and the failure of repeated cycles of antibiotics in the previous 12 months. At the initial consultation patients completed the NIH Prostatitis Symptoms Index (NIH-CPSI). All underwent:
- digital rectal examination (DRE),
- transrectal prostatic ultrasound scan (TRUS),
- uroflowmetry,
- cultures of first voiding and after prostatic massage urine and cultures of sperm for saprophytic and pathogen germs, yeasts and protozoa,
- DNA amplification with polymerase chain reaction (PCR) on urine and sperm, for Chlamydia trachomatis, Mycoplasmas (Ureaplasma urealyticum and Mycoplasma hominis), Gonococcus, HPV and HCV.
Patients on the basis of laboratory results received a cocktail of antibiotics associated with betamethasone. The cocktail was administered as prostate infiltration. Administration was repeated after 7 and 14 days. Final assessment of the effectiveness of therapy included not only the NIH-CPSI scores but also the patient's subjective judgement expressed as a "percentage overall improvement". The percentage judgements were arbitrarily divided into 4 classes:
- 0 to 30%: no improvement (Class I);
- 30 to 50%: satisfactory improvement (Class II);
- 50 to 80%: good improvement (Class III); and
- 80 to 100%: cured (Class IV).
Statistical analysis of the results showed 68% of patients were included in the Class IV and 13% were non-responders (Class I). The authors concluded that this is one of the more valid therapeutical approaches to chronic bacterial or abacterial prostatitis; but it also required more studies.
In a meta-analysis, Toulis et al. (2010) evaluated the diagnostic accuracy of inhibin B and AMH as markers of persistent spermatogenesis in men with non-obstructive azoospermia (NOA). A search was conducted in the electronic databases MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials from inception through June 2009. A total of 36 different studies reported data on the predictive value of one or more index markers (serum inhibin B: 32 studies, seminal inhibin B: 5 studies, serum AMH: 2 studies, seminal AMH: 4 studies) and were included in the systematic review. Nine studies, which had serum inhibin B as the index marker, met the predefined criteria and were included in the meta-analysis. Serum inhibin B showed a sensitivity of 0.65 (95% CI: 0.56 to 0.74) and a specificity of 0.83 (CI: 0.64 to 0.93) for the prediction of the presence of sperm in testicular sperm extraction (TESE). When the pre-test probability of 41% was incorporated in a Fagan's nomogram, it resulted in a positive post-test probability of 73% and a negative post-test probability of 23% for the presence of sperm in TESE. The authors concluded that serum inhibin B cannot serve as a stand-alone marker of persistent spermatogenesis in men with NOA. Although limited, evidence on serum AMH and serum/seminal AMH does not support their diagnostic value in men with NOA.
Current guidelines recommend hCG in men only for pituitary hypogonadism to address infertility issues. It is not recommended for long-term use outside of infertility treatment. The European Association of Urology’s guidelines on “Male Hypogonadism” (Dohle et al., 2012) noted that “In patients with secondary hypogonadism and fertility issues, and in selected cases of primary hypogonadism, hCG treatment can be chosen to support endogenous testosterone production for the period of infertility treatment. The dosage has to be adjusted individually to prevent suppression of FSH serum levels. hCG treatment has higher costs than testosterone treatment. There is insufficient information about the therapeutic and adverse effects of long-term hCG treatment. This type of treatment can therefore not be recommended for male hypogonadism, except in patients in whom fertility treatment is an issue.”
Chen et al. (2013) stated that reactive oxygen species (ROS) are an array of molecules, including oxygen-centered radicals, which are endowed with one or more unpaired electrons, and non-radical oxygen derivatives such as hydrogen peroxide, which behave, to a large extent, like a double-edged sword in human sperm biology. These investigators reviewed the current knowledge of ROS in sperm physiology and pathology, as well as related therapies in spermatozoal dysfunction. They searched for keywords from PUBMED, including reactive oxygen species, oxidative stress, sperm function, and antioxidant therapy. Low levels of ROS exert critical functions in normal sperm physiology, such as fertilizing ability (acrosome reaction, hyper-activation, capacitation, and chemotaxis) and sperm motility, while increased ROS generation and/or decreased antioxidant capacity leads to an imbalance between oxidation and reduction in living systems, which is called sperm oxidative stress. This condition is widely considered to be a significant contributory factor to sperm DNA damage/apoptosis, lipid peroxidation, and reduced motility, which, in turn, increases the risk of male factor infertility/subfertility and birth defects. Under the current status quo, numerous subsequent studies have concentrated on antioxidant therapy. Although the utility of such a therapeutic strategy has significantly improved sperm function and motility in a myriad of experimental and clinical reports, the overall effectiveness still remains controversial, mainly due to non-standardized assays to measure the level of ROS and sperm DNA damage, various antioxidant supplementation strategies, and inadequate fertilization and pregnancy data after clinical treatment. Therefore, standardized assessment and evaluation of ROS and total antioxidant capacity in semen should be established to keep ROS at a physiological level and prevent over-treatment of antioxidants toward reductive stress, which should be kept in mind, especially in assisted reproductive procedures. The authors noted that the significance of large sample size populations and double-blind randomized, placebo-controlled clinical trials of antioxidant therapies is emphasized in this review to achieve optimal ingredients and dosage of antioxidants for patients with reactive oxygen-induced male fertility/subfertility.
Yu and associates (2012) stated that numerous studies have reported cystic fibrosis transmembrane conductance regulator (CFTR) mutations in congenital bilateral absence of the vas deferens (CBAVD) patients, but their results are not completely consistent. These investigators performed a systematic review and meta-analysis with an emphasis on clarifying further the genetic association of CFTR mutations with CBAVD. They searched the Medline database until March 2011 for eligible articles reporting CFTR mutations in CBAVD. Relevant data from each included study were abstracted by two independent reviewers. The overall frequency of CFTR mutations in CBAVD and odds ratios (OR) for common specific alleles were pooled under random-effect or fixed-effect models as appropriate. Subgroup analysis was performed by ethnicity, and potential heterogeneity and bias were both assessed. Among CBAVD patients, 78% had at least one CFTR mutation, with 46% having two and 28% having only one. Moreover, the common heterozygous F508del/5T and F508del/R117H were observed in 17% and 4% of CBAVD cases, respectively, and the allele frequency in CBAVD was 17% for F508del, 25% for 5T, and 3% for R117H. Subgroup analysis indicated an increased frequency of cases with two mutations in Caucasian patients compared to non-Caucasian patients (68% versus 50%, p = 0.012), but no differences were found for cases with at least one mutation (88% versus 77%, p = 0.163) or with only one mutation (17% versus 25%, p = 0.115). Caucasian patients had a higher F508del frequency but a lower 5T frequency than non-Caucasian patients (22% versus 8%, p = 0.001; 20% versus 31%, p = 0.009). The summary OR was 9.25 for 5T [95% CI: 7.07 to 12.11, p = 0.000], with moderate heterogeneity (I² = 49.20%, p = 0.019) and evident bias (Egger's test, p = 0.005), and it was 19.43 for 5T/(TG)12_13 (95% CI: 10.48 to 30.03, p = 0.000) without any evidence of heterogeneity (I² = 0.1%, p = 0.391) and bias (Egger's test, p = 0.160). The OR for 5T/(TG)12_13 was significantly higher than that for the 5T allele (p = 0.000). The authors concluded that these findings demonstrated a high frequency of CFTR mutations in CBAVD patients, and these exhibited evident ethnic differences. In addition, the 5T allele and 5T/(TG)12_13 may contribute to the increased risk for CBAVD, with the 5T penetrance probably being modulated by adjacent (TG)12_13.
The European Association of Urology’s guidelines on “Male Infertility” (Jungwirth et al., 2012) stated that “Men with congenital bilateral absence of the vas deferens [CBAVD] often have mild clinical stigmata of cystic fibrosis (CF) (e.g., history of chest infections). Children born after intracytoplasmic sperm injection (ICSI), where the father has CBAVD and is either heterozygous or homozygous, must be followed up. When a man has CBAVD, it is important to test him and his partner for CF mutations. If the female partner is found to be a carrier of cystic fibrosis transmembrane conductance regulator (CFTR), the couple must consider very carefully whether to proceed with ICSI using the husband's sperm, as the risk of having a baby with CF will be 25% if the man is heterozygous and 50% if the man is homozygous. If the female partner is negative for known mutations, the risk of being a carrier of unknown mutations is about 0.4%.”
Sharma and co-workers (2014) noted that CF is usually considered a rare disease in the Indian population; two studies have reported on the frequency of CFTR gene mutations in Indian males with congenital absence of the vas deferens (CAVD). However, data on the spectrum of CFTR gene mutations are still lacking. These researchers identified the spectrum of CFTR gene mutations and investigated an association of CF genetic modifiers in the penetrance of CAVD in infertile Indian men. A total of 60 consecutive infertile males with a diagnosis of CAVD were subjected to CFTR gene analysis, which revealed 13 different CFTR gene mutations and one intronic variant that led to aberrant splicing. p.Phe508del (n = 16) and p.Arg117His (n = 4) were among the most common severe forms of CFTR mutations identified. The IVS8-T5 allele, which is considered a mild form of CFTR mutation, was found with an allelic frequency of 28.3%; eight novel mutations were also identified in the CFTR gene from this patient cohort. It was noteworthy that the spectrum of CFTR gene mutations was heterogeneous, with exon 4 and exon 11 as hotspot regions. Moreover, these investigators also found an association of the CF genetic modifiers, namely transforming growth factor (TGF)-β1 and endothelial receptor type-A (EDNRA) genes, with the CAVD phenotype. The findings were of considerable clinical significance because men suffering from infertility due to CAVD can decide to use artificial reproduction technology. The children of men with CAVD are at risk of carrying CFTR mutations; therefore, genetic counseling is a crucial step for such patients. With special reference to developing countries, such as India, where whole gene sequencing is not feasible, the outcome of this study will make the screening procedure for CFTR gene simpler and more cost-effective, as these researchers have identified hotspot regions of the CFTR gene that are more prone to mutation in Indian males with CAVD. Moreover, this was the first study from the Indian population to investigate the association of CF genetic modifiers with the penetrance of the CAVD phenotype. They stated that the observed association of the genetic modifiers TGF-β1 and EDNRA in the penetrance of CAVD further supports their involvement in the genesis of the vas deferens.
Yang and colleagues (2015) discussed the findings and significance of the detection of the CFTR gene mutation in azoospermia patients with congenital unilateral absence of the vas deferens (CUAVD). These researchers collected peripheral blood samples from six azoospermia patients with CUAVD for the detection of CFTR gene mutations and single nucleotide polymorphisms (SNPs). They analyzed the genome sequences of the CFTR gene in comparison with the website of the UCSC Genome Browser on Human December 2013 Assembly. A missense mutation of c. 592G > C in exon 6 was found in one of the six azoospermia patients with CUAVD, and a splicing mutation of c. 1210-12T[5] was observed in the non-coding region before exon 10 in two of the patients, both with the V470 haplotype in exon 11. The authors concluded that mutations of the CFTR gene can be detected in azoospermia patients with CUAVD, and the detection of the CFTR gene mutation is necessary for these patients.
Zhang et al. (2015) stated that the CAG repeat in the polymerase γ (POLG) gene, which encodes polymerase γ for mitochondria, is important for spermatogenesis. Compared with a few researchers who raised concerns about the alteration of CAG repeat-affected male reproductive ability, others did not find an association between CAG repeat polymorphisms and male infertility. These researchers performed a comprehensive meta-analysis to determine the association; 13 case-control studies were screened out using keyword searches. From these studies, characteristics were extracted for conducting the meta-analysis. Odds ratio (OR) and 95% confidence interval (CI) were used to describe the results; the results indicated that the CAG repeat allele was not a risk factor for male infertility (pooled OR = 1.03, 95% CI: 0.79 to 1.34, p = 0.828). Four different genetic comparisons also demonstrated a negative result: heterozygote comparison (not 10/10 versus 10/10; pooled OR = 0.99, 95% CI: 0.77 to 1.27, p = 0.948), homozygote comparison (not 10/not 10 versus 10/10; pooled OR = 1.08, 95% CI: 0.56 to 2.06, p = 0.816), the recessive genetic comparison (not 10/not 10 versus not 10/10 + 10/10; pooled OR = 1.07, 95% CI: 0.58 to 1.95, p = 0.829), and the dominant genetic comparison (not 10/not 10 + not 10/10 versus 10/10; pooled OR = 0.97, 95% CI: 0.72 to 1.29, p = 0.804). The authors concluded that based on current research, this meta-analysis demonstrated no apparent association between POLG-CAG repeat and male infertility. Similarly, the CAG repeat was not a sensitive site for male infertility.
Cao and colleagues (2019) stated that a number of studies have been carried out to examine the relationship between the CYP1A1 rs4646903 polymorphism and male infertility risk, but the sample size was small and the results were conflicting. These researchers conducted a meta-analysis to examine these associations. They performed a systematic search to identify all relevant studies from Medline, Web of Science, Embase, China Biology Medical Literature Database (CBM), China National Knowledge Infrastructure (CNKI), WanFang, and Weipu (VIP) databases up to June 30, 2018. The ORs with 95% CIs were calculated to assess the strength of associations. All of the statistical analyses were conducted using Revman 5.3 and Stata 14.0. A total of 10 studies entailing 3,028 cases and 3,258 controls were included in this analysis. Overall, a significant association was observed between the CYP1A1 rs4646903 polymorphism and male infertility (C versus T: OR = 1.42, 95% CI: 1.14 to 1.76; CC versus TT: OR = 2.13, 95% CI: 1.36 to 3.34; CC versus CT+TT: OR = 1.96, 95% CI: 1.30 to 2.95; CC+CT versus TT: OR = 1.51, 95% CI: 1.16 to 1.97). In subgroup analysis by ethnic group, a statistically significant association was observed in Asians (C versus T: OR = 1.59, 95% CI: 1.22 to 2.08), but not in non-Asians (C versus T: OR = 1.01, 95% CI: 0.79 to 1.30). Furthermore, none of the individual studies significantly affected the association between CYP1A1 rs4646903 polymorphism and male infertility, according to sensitivity analysis. The authors concluded that the findings of this meta-analysis supported that the CYP1A1 rs4646903 polymorphism might contribute to individual susceptibility to male infertility in Asians. Moreover, these researchers stated that large sample size, well-designed, and population-based studies are needed to validate the association between the CYP1A1 gene variant rs4646903 polymorphism and male infertility risk.
The authors stated that this study had several drawbacks. First, only 10 studies were incorporated in the meta-analysis; the sample size of included published articles was small. Second, subgroup analyses such as by infertility type and source of control group were not performed due to the lack of information. Third, the effects of gene-gene and gene-environment interactions on male infertility susceptibility were not estimated, as the studies enrolled lacked information. Finally, these findings were based on unadjusted estimates due to the lack of data on smoking, age, and other environmental exposure factors.
Asgari and colleagues (2019) noted that studies suggested that FAS/FASL polymorphisms are associated with male infertility; however, their results are still inconclusive. In a systematic review and meta-analysis, these researchers examined the overall association of FAS/FASL polymorphisms and the risk of male infertility. They carried out a search on the databases of Science Direct, PubMed, and Google Scholar. For performing the meta-analysis, pooled OR values with 95% CI were applied in order to analyze the strength of the association between the FAS/FASL polymorphisms and the risk of male infertility. A total of seven relevant studies published up to September 2018 were considered. FASL-844C/T genotype results of 559 patients and 623 healthy individuals were included in this study. For FAS-670A/G genotype effect, 751 patients and 821 healthy individuals were examined. Results showed that all analysis models, including dominant, recessive, and allelic models of FASL-844C/T and FAS-670A/G polymorphism, had no significant effect on infertility in men (p > 0.05 and p > 0.05, respectively). According to sensitivity analysis, these findings were stable. The authors demonstrated that FAS/FASL polymorphisms might not be an effective factor on male reproductive health. These researchers stated that for precise determination of FAS/FASL polymorphisms' effects on male infertility, large-scale, case-control studies are needed.
Ovarian Reserve and Age-Related Prognosis
Ovarian reserve is defined as the number of oocytes remaining in the ovary, or oocyte quantity (oocyte number). Ovarian reserve, or oocyte quantity (oocyte number), is different from oocyte quality, which relates to the potential of a fertilized oocyte to result in a live-born infant.
ASRM recommends ovarian reserve assessment as part of a comprehensive diagnostic workup, particularly in individuals at increased risk for reduced reproductive potential, such as those of advanced reproductive age or with a history of ovarian surgery, gonadotoxic therapy, or genetic conditions associated with accelerated follicular depletion. Importantly, ASRM cautions that ovarian reserve tests should not be used as standalone predictors of fertility or to categorically deny access to infertility treatment, but rather to inform prognosis, counseling, and individualized clinical decision‑making within an evidence‑based framework.
Ovarian reserve assessment relies on a combination of biochemical markers and ovarian ultrasound imaging to estimate the size of the remaining follicular pool. Biochemical tests include early‑follicular‑phase measurements of follicle‑stimulating hormone (FSH), estradiol (E2), and inhibin B; cycle‑independent measurement of anti‑Müllerian hormone (AMH); and less commonly used provocative tests, such as the clomiphene citrate challenge test (CCCT). These measures aim to directly or indirectly reflect oocyte quantity rather than quality. AMH and inhibin B, both glycoproteins produced by small ovarian follicles, are considered more direct indicators of the follicular pool, with AMH primarily secreted by primary, preantral, and early antral follicles and inhibin B mainly by preantral follicles. As follicle number declines with age, circulating levels of AMH and early‑follicular inhibin B decrease, leading to reduced negative feedback on the pituitary and a compensatory rise in FSH levels, which serves as an indirect marker of diminished ovarian reserve. This hormonal cascade is also associated with earlier follicular recruitment, increased early‑cycle estradiol levels, and shortening of the follicular phase, forming the physiological basis for the clinical use of these tests as markers of ovarian reserve (ASRN, 2020).
No fertility treatment other than oocyte donation has been shown to be effective for women over 40 years of age with compromised ovarian reserve. Elevated FSH and estradiol levels are independent predictors of poor prognosis in older women. Common criteria for normal ovarian reserve are an early follicular phase FSH level of less than 10 mIU/ml and an estradiol level of less than 80 pg/ml (ASRM, 2002). Higher cut-off values for FSH have been reported (as high as 20 to 25 mIU/ml for FSH) because of the use of different FSH assay reference standards. Women with diminished ovarian reserve experience decreased responses to ovulation induction, require higher doses of gonadotropin, have higher in-vitro fertilization (IVF) cycle cancellation rates, and experience lower pregnancy rates through IVF.
Biomarkers of Ovarian Reserve (AMH, FSH, AFC, Inhibin B)
Basal serum follicle‑stimulating hormone (FSH) and estradiol (E2), clomiphene citrate challenge testing, anti‑Müllerian hormone (AMH), and ultrasonographic measures such as antral follicle count (AFC) are used to assess ovarian reserve, with varying clinical utility. Elevated early‑follicular‑phase FSH levels (cycle days 2–4) are a specific but insensitive marker of diminished ovarian reserve (DOR) and are limited by substantial inter‑ and intra‑cycle variability, while basal E2 alone is not a reliable screening test but may aid interpretation of a normal FSH when E2 is elevated, potentially masking underlying DOR. The clomiphene citrate challenge test was developed to improve sensitivity by assessing stimulated FSH response; however, evidence indicates it is not superior to basal testing or AFC for predicting ovarian response or pregnancy outcomes and is therefore no longer recommended. In contrast, AMH, a gonadotropin‑independent hormone produced by granulosa cells of early follicles, demonstrates low cycle‑to‑cycle variability and greater sensitivity for early declines in ovarian reserve, preceding FSH elevation, and has largely replaced basal FSH and E2 as the preferred biochemical marker, with the latter providing adjunctive information in select cases of very low AMH. Ultrasonographically, AFC, defined as the number of 2–10 mm follicles visualized in both ovaries during the early follicular phase, is a reliable and reproducible measure of ovarian reserve in experienced centers, whereas ovarian volume is less commonly used due to limited sensitivity and higher variability, making AMH and AFC the primary contemporary markers informing ovarian reserve assessment in infertility evaluation and policy contexts (ASRM, 2020).
Steiner (2009) stated that serum and urinary markers of ovarian reserve – follicular phase inhibin B, FSH, and anti-mullerian hormone (AMH) levels – are physiologically associated with ovarian aging, decline with chronologic age, and appear to predict later stages of reproductive aging including the menopause transition and menopause. In infertile women, they can be used to predict low oocyte yield and treatment failure in women undergoing IVF. These markers seem to be affected by common ovarian toxicants, such as smoking, which advance the age at menopause. Although available for commercial use, home test kits have not been shown to predict fertility or infertility in the general population. Clinical use of these markers is limited by the variety of assays, lack of definitive thresholds, and their intercycle variability in older women. Results should be conveyed with caution when highly discrepant with age, in the obese, and in women with irregular menstrual cycles. The author stated that further research is needed to assess their predictive value for determining fertility in the general population.
Nelson et al. (2009) stated that individualization of controlled ovarian stimulation (COS) for assisted conception is complicated by variable ovarian response to FSH. These researchers hypothesized that AMH may facilitate treatment strategies for women undergoing COS, to optimize safety and clinical pregnancy rates. A prospective cohort study of 538 patients in 2 centers with differential COS strategies based on a centralized AMH measurement was performed. Anti-Mullerian hormone was associated with oocyte yield after ovarian stimulation in both centers, and a "reduced" AMH (1 to less than 5 pmol/L) was associated with a reduced clinical pregnancy rate. Women with a "normal" AMH (5 to less than 15 pmol/L) treated with a long GnRH-agonist protocol (both centers) showed a low incidence of excess response (0%) and poor response (0%). In women with "high" AMH (greater than 15 pmol/L), the antagonist protocol eliminated the need for complete cryo-preservation of embryos due to excess response (p < 0.001) and showed a higher fresh cycle clinical pregnancy rate than agonist cycles odds ratio (OR) 4.40 (95% confidence interval [CI]: 1.95 to 9.93), p < 0.001]. The authors concluded that the use of circulating AMH to individualize treatment strategies for COS may result in reduced clinical risk, optimized treatment burden and maintained pregnancy rates, and is worthy of prospective randomized examination.
Nardo et al. (2009) evaluated the clinical value of basal AMH measurements compared with other available determinants, apart from chronologic age, in the prediction of ovarian response to gonadotrophin stimulation. Women undergoing their first cycle of controlled ovarian hyperstimulation (COH) for IVF were subject of this study. Basal levels of FSH and AMH as well as antral follicle count (AFC) were measured in 165 subjects. All patients were followed prospectively and their cycle outcomes recorded. Main outcome measures included predictive value of FSH, AMH, and AFC for extremes of ovarian response to stimulation. Out of the 165 women, 134 were defined as normal responders, 15 as poor responders, and 16 as high responders. Subjects in the poor response group were significantly older then those in the other 2 groups. Anti-Müllerian hormone levels and AFC were markedly raised in the high responders and decreased in the poor responders. Compared with FSH and AFC, AMH performed better in the prediction of excessive response to ovarian stimulation-AMH area under receiver operating characteristic curve (ROC(AUC)) 0.81, FSH ROC(AUC) 0.66, AFC ROC(AUC) 0.69. For poor response, AMH (ROC(AUC) 0.88) was a significantly better predictor than FSH (ROC(AUC) 0.63) but not AFC (ROC(AUC) 0.81). Anti-Mullerian hormone prediction of ovarian response was independent of age and polycystic ovarian syndrome (PCOS). Anti-Mullerian hormone cutoffs of greater than 3.75 ng/ml and less than 1.0 ng/ml would have modest sensitivity and specificity in predicting the extremes of response. The authors concluded that circulating AMH has the ability to predict excessive and poor response to stimulation with exogenous gonadotrophins. Overall, this biomarker is superior to basal FSH and AFC, and has the potential to be incorporated in to work-up protocols to predict patient's ovarian response to treatment and to individualize strategies aiming at reducing the cancellation rate and the iatrogenic complications of COH.
Su and associates (2010) examined if AMH and inhibin B were impacted by breast cancer treatment by comparing cancer survivors to age-matched control women and determined the association between these hormones and post-chemotherapy menstrual pattern. Breast cancer patients (n = 127) with American Joint Committee on Cancer stage I to III disease who were pre-menopausal at diagnosis were enrolled post-chemotherapy and observed. The primary end point was chemotherapy-related amenorrhea (CRA) (greater than or equal to 12 months of amenorrhea following chemotherapy). Matched pair analyses compared AMH, inhibin B, and FSH levels between cancer and age-matched control subjects. Associations between hormones, CRA status, and change in CRA status over time were assessed. The median age of the patients at chemotherapy was 43.2 years (range of 26.7 to 57.8 years). At enrollment, median follow-up since chemotherapy was 2.1 years, and 55% of subjects had CRA. Compared with age-matched controls, cancer subjects had significantly lower AMH (p = 0.004) and inhibin B (p < 0.001) and higher FSH (p < 0.001). Inhibin B (p = 0.001) and AMH (p = 0.002) were found to be significantly associated with risk of CRA, even after controlling for FSH. Anti-mullerian hormone was significantly lower (p = 0.03) and FSH was significantly higher (p = 0.04) in menstruating subjects who developed subsequent CRA. The authors concluded that AMH and inhibin B are 2 additional measures of post-chemotherapy ovarian function in late reproductive-aged breast cancer survivors. They stated that with further research and validation, these hormones may supplement limited current tools for assessing and predicting post-chemotherapy ovarian function.
Steiner et al. (2011) generated estimates of the association between markers of ovarian aging and natural fertility in a community sample at risk for ovarian aging. Women aged 30 to 44 years with no history of infertility who had been trying to conceive for less than 3 months provided early-follicular phase serum and urine (n = 100). Subsequently, these women kept a diary to record menstrual bleeding and intercourse and conducted standardized pregnancy testing for up to 6 months. Serum was analyzed for estradiol, FSH, AMH, and inhibin B. Urine was analyzed for FSH and estrone 3-glucuronide. Diary data on menstrual cycle day and patterns of intercourse were used to calculate day-specific fecundability ratios. Sixty-three percent of participants conceived within 6 months. After adjusting for age, 18 women (18%) with serum AMH levels of 0.7 ng/ml or less had significantly reduced fecundability given intercourse on a fertile day compared with women with higher AMH levels (fecundability ratio 0.38; 95% CI: 0.08 to 0.91). The day-specific fecundability for women with early-follicular phase serum FSH values greater than 10 mIU/ml compared with women with lower FSH levels was also reduced, although nonsignificantly (11% of women affected; fecundability ratio 0.44; 95% CI: 0.08 to 1.10). The association with urinary FSH was weaker (27% women affected; fecundability ratio 0.61; 95% CI: 0.26 to 1.26), and the associations for the other markers were weaker still. The authors concluded that early-follicular phase AMH appears to be associated with natural fertility in the general population. Moreover, they stated that larger studies are needed to confirm these findings and to explore the way the different endocrine markers interact as potential joint predictors of fertility.
Can et al. (2024) stated that antral follicle count (AFC) and serum AMH are currently the most sensitive and reliable markers of ovarian reserve; however, the role of AFC and AMH as prognostic markers of diminished ovarian reserve (DOR) in pregnancy outcomes after embryo transfer (ET) has been inconsistent. These investigators carried out a retrospective cohort study in a university-affiliated hospital. A total of 4,599 women who received their first IVF treatment between January 2012 and December 2019 were included. Uni- and multivariable regression models were used to determine the association of DOR evaluated by AFC and AMH with pregnancy, number of ET cycles to pregnancy, live birth, preterm birth (PTB), and low birth weight. Among the women included, 380 (8.3%) had DOR (i.e., AFC of less than 5 or AMH of less than 1.2 μg/L). After adjusting for confounders, DOR determined by AFC/AMH, AFC alone, and AMH alone was associated with a lower pregnancy rate (risk ratio [RR] 0.81, 95% confidence interval [CI]: 0.73 to 0.89). Among women who were successfully pregnant, DOR evaluated by AFC/AMH, but not evaluated by AFC alone or AMH alone, was associated with an increased number of ET cycles to pregnancy (odds ratio [OR] 1.43, 95% CI: 1.04 to 1.96). DOR was not associated with the risks of live birth, low birth weight, or PTB. Women with DOR may have more difficulty becoming pregnant after IVF treatment, suggesting the predictive role of DOR in pregnancy outcomes before IVF treatment.
Sukur et al. (2024) noted that AMH is a widely used marker for estimating ovarian reserve, and it may predict response to ovarian stimulation. While AMH is considered a stable, cycle-independent marker, studies have shown it can exhibit significant fluctuations based on factors like age, reproductive stage, and menstrual cycle phase. The fluctuations in AMH levels can make it challenging to predict individual responses accurately, especially when the AMH is not measured in the controlled ovarian stimulation (COS) cycle. In a retrospective, single-center study, these researchers examined the inter-cycle variability of serum AMH levels in two consecutive menstrual cycles and their correlation with response to controlled ovarian stimulation outcomes in the latter. This trial included data from normal and low-responder patients who underwent intra-cytoplasmic sperm injection (ICSI) following a GnRH antagonist cycle at a university hospital infertility clinic between January 2022 and December 2023. Serum AMH levels were measured in the early follicular phase of two consecutive menstrual cycles with the Elecsys-AMH Roche system (Roche Diagnostics, Meylan, France). Correlations between AMH levels and controlled ovarian stimulation outcomes, including total oocyte and mature oocyte (MII) counts, were assessed. The study included normal and poor-responder women to maintain data integrity. A total of 79 patients were included in the final analyses. Significant cycle-to-cycle variation in serum AMH levels was observed, with a median variation of 44.3%. Normal responders exhibited a mean change of 0.60 ± 0.46 ng/ml, while poor responders had a mean change of 0.28 ± 0.28 ng/ml. Approximately 20% of patients were reclassified between normal and poor responder categories based on the second AMH measurement. The COS cycle AMH levels showed a stronger correlation with both total oocyte count (r = 0.871, p < 0.001) and MII oocyte count (r = 0.820, p < 0.001) compared to preceding cycle AMH levels. The authors concluded that AMH levels could exhibit significant variations between consecutive cycles, potentially resulting in misclassification of patients. These investigators stated that measuring AMH in the early follicular phase of the COS cycle provided a more accurate prediction of the numbers of total and MII oocytes collected. Consistent and repeated AMH measurements can aid in clinical decision-making.
Teng et al. (2024) stated that women with DOR have significantly lower cumulative live birth rates (CLBRs) than women with normal ovarian reserve. A subset of young infertile patients, whose ovarian reserve is declining but has not yet met the POSEIDON criteria for DOR, has not received the attention it merits. These individuals have not been identified in a timely manner before the initiation of assisted reproductive technology (ART), resulting in suboptimal clinical pregnancy outcomes. These researchers categorized this overlooked cohort as the "high-risk DOR" group. They identified high-risk DOR patients through AMH and AFCs. A total of 10,037 young women (35 years old or younger) who underwent their first initial oocyte aspiration cycle at a single reproductive medicine center were included and further classified into three groups based on the thresholds for AMH and AFC established through receiver operating characteristic (ROC) analysis and in alignment with the POSEIDON criteria. Two ROC analyses were carried out to identify the cut-off values of AMH and AFC to obtain one viable embryo (one top-quality embryo or one viable blastocyst). The cut-offs of ROC were measured by sensitivity and specificity. The primary outcome was the CLBR per oocyte aspiration cycle. The secondary outcomes included the number of oocytes retrieved and the number of viable embryos formed. Pearson's Chi-square tests were performed to compare the clinical outcomes among the three groups. In addition, univariate logistic regression analyses were carried out to examine the associations between ovarian reserve and clinical outcomes. All of the above comparisons between the high-risk DOR and normal ovarian reserve (NOR) were further confirmed by propensity score matching (PSM) (1:1 nearest-neighbor matching, with a caliper width of 0.02). According to the ROC analyses and POSEIDON criteria, this trial identified a population of high-risk DOR patients (1.20 ng/mL < AMH values < 2.50 ng/mL, with 6 ≤ AFC ≤ 10; n = 682), and their outcomes were further compared to those of DOR patients (positive control, AMH values ≤ 1.2 ng/mL, and/or AFC ≤ 5; n = 1,153) and of NOR patients (negative control, 2.5 ng/mL ≤ AMH values ≤ 5.5 ng/mL, and 11 ≤ AFC ≤ 20; n = 2,649). Patients in the high-risk DOR group had significantly lower CLBRs than those in the NOR group (p < 0.001) but higher CLBRs than those in the DOR group (p < 0.001). Logistic regression further showed that high-risk DOR was associated with a lower likelihood of cumulative live birth chance (OR 0.401, 95% CI: 0.332 to 0.486, p < 0.001) than NOR was, with a greater likelihood of cumulative live birth chance (OR 1.911, 95% CI: 1.558 to 2.344, p < 0.001) than DOR was. To examine the effects of embryo development stage, the outcomes of D3 embryos and blastocysts were analyzed separately. Significant differences in pregnancy outcomes were detected only in D3 embryo ET cycles among the three groups (high-risk DOR versus NOR, all p < 0.05; DOR versus NOR, all p < 0.05). DOR/high-risk DOR did not influence the pregnancy loss rates or pregnancy outcomes (clinical pregnancy rates and ongoing pregnancy rates) per positive HCG cycle (all p > 0.05). After PSM, the differences in ovarian response and pregnancy outcomes between the high-risk DOR and NOR groups were consistent with the results before PSM. The authors concluded that the findings of this study showed that the CLBR of the high-risk DOR patients was significantly lower than that of women with normal ovarian reserve and greater than that of women with DOR. The values of AMH ranging from 1.2 to 2.5 ng/mL and AFC ranging from 6 to 10 appeared to constitute meaningful thresholds in women with mildly reduced ovarian reserve.
Immunologic and Autoimmune Factors in Infertility
Studies evaluating natural killer cells, T regulatory cells, cytokine ratios, and antiphospholipid antibodies suggest potential associations with infertility and pregnancy loss; however, available evidence does not support routine clinical testing or treatment. Reviews by Ly et al. (2010), McGrath et al (2009), Winger et al. (2011), and Chighizola and de Jesus (2014) consistently conclude that these immunologic markers lack validated clinical utility outside of recurrent pregnancy loss related to antiphospholipid syndrome.
McGrath et al. (2009) stated that cycle-dependent fluctuations in natural killer (NK) cell populations in endometrium and circulation may differ, contributing to unexplained infertility. They conducted a study whereby NK cell phenotypes were determined by flow cytometry in endometrial biopsies and matched blood samples. While circulating and endometrial T cell populations remained constant throughout the menstrual cycle in fertile and infertile women, circulating NK cells in infertile women increased during the secretory phase. However, increased expression of CD94, CD158b (secretory phase), and CD158a (proliferative phase) by endometrial NK cells from infertile women was observed. These changes were not reflected in the circulation. In infertile women, changes in circulating NK cell percentages were found exclusively during the secretory phase and not in endometrium; cycle-related changes in NK receptor expression were observed only in infertile endometrium. While having exciting implications for understanding NK cell function in fertility, these data emphasized the difficulty in attaching diagnostic or prognostic significance to NK cell analyses in individual patients.
Winger et al. (2011) examined if quantification of peripheral blood Treg cell levels could be used as an indicator of miscarriage risk in newly pregnant women with a history of immunologic reproductive failure. A total of 54 pregnant women with a history of immunologic infertility and/or pregnancy loss were retrospectively evaluated (mean age of 36.7 +/- 4.9 years, 2.8 +/- 2.5 previous miscarriages; 1.5 +/- 1.9 previous IVF failures). Twenty-three of these women experienced another first trimester miscarriage, and 31 of these women continued their current pregnancies past 12 weeks ("pregnancy success"). The following immunologic parameters were assessed in the first trimester: NK cell 50:1 cytotoxicity, CD56(+) 16(+) CD3(-) (NK), CD56(+) CD3(+) (NKT), TNFα/IL-10, IFNγ/IL-10, CD4(+) CD25(-) Foxp3(+), total CD4(+) Foxp3(+) (CD4(+) CD25(+) Foxp3 plus CD25(-) Foxp3(+)), and CD4(+) CD25(+) Foxp3(+) levels. Patients with successful ongoing pregnancies experienced a mean (CD4(+) CD25(+) Foxp3(+)) "Treg" level of 0.72 +/- 0.52%, while those that miscarried in the first trimester experienced a mean Treg level of 0.37 +/- 0.29% (p = 0.005). Markers not significantly different between the loss and success groups were NK 50:1 cytotoxicity (p = 0.63), CD56(+) 16(+) 3(+) NK cells (p = 0.63), CD56(+) 3(+) NKT (p = 0.30), TNFα(+) IL-10(+) (p = 0.13), IFNg(+) IL-10(+) (p = 0.63), and CD4(+) 25(-) Foxp3(+) cells (p = 0.10), although total CD4(+) Foxp3(+) levels remained significant (p = 0.02) and CD4(+) 25(+) Foxp3(+) showed the most significant difference (p = 0.005). Mean day of blood draw was 49.2 +/- 36.1 days pregnant (median of 39.0 days). In addition, patients with a low Treg level (less than 0.7 %) in the first trimester experienced a significantly lower ongoing pregnancy rate than those with a higher Treg level (greater than 0.7%) in the first trimester [44% (15/34) versus 80% (16/20); p = 0.01]. Of the 18 successful pregnancies with sequential Treg results, 85% (11/13) showed a T-regulatory-cell-level increase (mean Treg change 0.33 +/- 0.32), while only 40% (2/5) of the failed pregnancies showed a Treg increase (mean Treg change -0.08 +/- 0.28; p = 0.02). The authors concluded that from these data, they proposed that CD4(+) CD25(+) Foxp3(+) T regulatory cells may serve as a superior pregnancy marker for assessing miscarriage risk in newly pregnant women. Moreover, they stated that larger follow-up studies are needed for confirmation.
Chighizola and de Jesus (2014) noted that since the late 1980s, some publications have proposed that antiphospholipid antibodies (aPL) may have some relationship with infertility, considering the reported deleterious effects that aPL exert on trophoblast proliferation and growth. Although not included in current classification criteria for antiphospholipid syndrome, many physicians investigate aPL in patients with a history of infertility, including antibodies not listed in classification criteria, and most of those patients will receive anticoagulant therapy if any of those antibodies have a result considered positive. These investigators performed a review of the literature, searching for studies that investigated the association of aPL and infertility and whether aPL positivity alters IVF outcomes. The definition of infertility, routine work-up to exclude other causes of infertility, definition of IVF failure as inclusion criteria, and control populations were heterogeneous among studies. Most of them enrolled women over 40 years of age, and the exclusion of other confounding factors was also inconsistent. Of 29 studies that assessed aPL positivity rates in infertile women, the majority had small sample sizes, implying a lack of power, and 13 (44.8%) reported a higher frequency of aPL in infertile patients compared to controls, but most of them investigated a panel of non-criteria aPL tests, whose clinical significance is highly controversial. Only two studies investigated all three criteria tests, and a medium-high titer of anticardiolipin cut-off conforming to international guidelines was used in one study. Considering IVF outcomes, there was also disparity in this definition: few studies assessed the live birth rate, while others assessed the implantation rate. Of 14 publications that addressed the relationship between aPL and IVF outcomes, only two described a detrimental effect of these autoantibodies. The authors concluded that available data do not support an association between aPL and infertility, and aPL positivity does not seem to influence IVF outcomes. They stated that well-designed clinical studies recruiting women with a clear diagnosis of infertility and a high-risk aPL profile should be performed to test whether clinically relevant aPL do or do not exert an effect on human fertility.
There is some evidence that in women with high T-helper 1/T-helper 2 (Th1/Th2) ratios, there is an increased incidence of pregnancy loss and infertility. Thus, this test has been used by infertility specialists. However, there are no studies demonstrating the clinical utility of these measurements. A review by Ly et al. (2010) stated: “Th1 dominance may well be a result of the miscarriage rather than a cause, and much more basic knowledge is needed about the complex cytokine networks in pregnancy and the correlation between cytokine production in peripheral mononuclear cells and decidual lymphocytes before tests measuring cytokines can be introduced in clinical practice.”
Ozkan et al. (2014) noted that implantation necessitates complex interactions among the developing embryo, decidualizing endometrium, and developing maternal immune tolerance and/or alterations in cellular and humoral immune responses. Overstimulation of Th1 or Th2 cytokines in systemic and local environments, as well as alterations in the prevalence of interleukin-17 (IL-17) and regulatory T cell (Treg) cytokines, have also been suggested to contribute to the pathogenesis of implantation failure. These researchers investigated the plasma levels of IL-4, IL-6, IL-10, tumor necrosis factor-alpha (TNFα), gamma interferon (IFNγ), transforming growth factor-beta (TGFβ), IL-17, IL-35, and suppressors of cytokine signaling 3 (SOCS3) in infertile and fertile women. This case-control study was conducted with 80 women suffering from unexplained infertility and 40 fertile women. Peripheral venous blood samples were drawn on day 21 of the menstrual cycle. The extracted plasma samples were assayed by an enzyme-linked immunosorbent assay (ELISA). Statistical analysis was performed using SPSS version 16.0. The main findings were as follows: despite the significantly high IL-17 and IL-35 plasma levels in infertile women, the IL-35/IL-17 ratio was significantly lower in the infertile group compared with that in the fertile group; SOCS3 plasma levels showed an inverse relationship with plasma levels of all cytokines except IL-35; increased plasma IL-17 levels (greater than 3.42 pg/ml) have a negative impact on fertility; and TNFα/IL-10, IFNγ/IL-10, IFNγ/IL-6, and IFNγ/IL-4 ratios were significantly higher in the infertile group compared with those in the fertile group. The authors concluded that it is not possible to show the major immunological factor(s) of unexplained infertility, but these findings pointed out that the decreased suppressor activity of the immune system may play a role in implantation failure.
Ovarian Stimulation
Ovarian stimulation is an established infertility treatment strategy used to induce or enhance follicular development in order to facilitate ovulation or to obtain multiple oocytes for assisted reproductive technologies (ART). According to the American Society for Reproductive Medicine (ASRM), ovarian stimulation may be achieved using oral agents (such as clomiphene citrate or letrozole) for ovulation induction or exogenous gonadotropins for controlled ovarian stimulation in intrauterine insemination (IUI) and in vitro fertilization (IVF) cycles, with the goal of augmenting endogenous gonadotropin activity to overcome ovulatory dysfunction or improve treatment efficiency. Stimulation protocols are individualized based on patient‑specific factors including age, infertility diagnosis, ovarian reserve, and prior treatment response, in order to optimize outcomes while minimizing risks. The principal risks associated with ovarian stimulation include multifetal gestation and ovarian hyperstimulation syndrome (OHSS), the latter resulting from increased vascular permeability and fluid shifts; however, ASRM notes that contemporary evidence‑based strategies—such as individualized dosing, GnRH antagonist protocols, and modified ovulation triggers—have significantly reduced the incidence and severity of OHSS. Overall, ASRM classifies ovarian stimulation as a non‑experimental, evidence‑supported intervention when applied using established protocols and appropriate patient selection, emphasizing the importance of balancing efficacy with maternal and fetal safety (ASRM, 2016; ASRM, 2020).
Aetna covers ovarian stimulation medications and techniques only for women with a biologic capacity to effectively respond to ovarian stimulation. Serum FSH is used as a marker of ovarian responsiveness. Ovarian responsiveness is determined by an unmedicated day 3 FSH measurement obtained within 6 months for women older than age 35 and within 12 months for women age 35 or younger. In women older than age 40, any single day 3 FSH value greater than 19 mIU/mL is indicative of ovarian insufficiency, regardless of subsequent lower measurements. In women under age 40, ovarian responsiveness is demonstrated by any unmedicated day 3 FSH value less than 19 mIU/mL.
Follitropins and Menotropins
For follitropins and menotropins, see CPB 1082 - Follitropins and Menotropins.
Human Chorionic Gonadotropin
For human chorionic gonadotropin (hCG), see CPB 1081 - Human Chorionic Gonadotropin (hCG).
Assisted Reproductive Technologies and Adjunctive Interventions
In a Cochrane review, Duffy et al. (2010) evaluated the effectiveness of adjuvant growth hormone (GH) in IVF protocols. A total of 10 studies (440 subfertile couples) were included. Results demonstrated no difference in outcome measures or adverse events with routine use of GH; however, a statistically significant improvement in live birth and pregnancy rates was observed in poor responders. The authors concluded that although GH may improve outcomes in poor responders, further research is needed to define its role.
In a meta-analysis, Polyzos and associates (2010) examined the effect of double versus single intra-uterine insemination (IUI) per treatment cycle in women with unexplained infertility. Main outcome measure was clinical pregnancy rates per couple. Electronic searches of the Cochrane Central Trials Registry and Medline without year and language restriction through March 2009 were performed; hand searching of the abstract books of the European Society of Human Reproduction and Embryology and American Society for Reproductive Medicine annual meetings (2001 to 2008) was carried out. A total of 6 randomized trials, involving 829 women, were included in the analysis. Fifty-four (13.6%) clinical pregnancies were recorded for treatment with double IUI and 62 (14.4%) for treatment with single IUI. There was no significant difference between the single and double IUI groups in the probability for clinical pregnancy (OR, 0.92; 95% CI: 0.58 to 1.45; p = 0.715). The authors concluded that double IUI offers no clear benefit in the overall clinical pregnancy rate in couples with unexplained infertility.
Multiple systematic reviews and randomized trials evaluating luteal phase support, hCG supplementation, endometrial thickness, functional ovarian cyst aspiration, and in vitro maturation consistently demonstrate limited or inconsistent benefit, with methodological limitations and potential risks such as ovarian hyperstimulation syndrome.
In a prospective, randomized controlled trial, Ben-Meir et al. (2010) examined if supplementation with hCG throughout the secretory phase of hormonally modulated cycles of frozen-thawed embryos might positively affect the outcome of such cycles. Patients were randomly divided into 2 groups by the last digit of their identification number. Group A received the authors’ standard protocol for endometrial preparation, whereas group B patients were given an additional 250 microg of recombinant hCG on day of progesterone (P) initiation, the day of embryo transfer, and 6 days later. Throughout the cycle, and to compare between the groups, serial ultrasound examinations and hormonal tests of E(2) and P serum levels were obtained. Main outcome measures were implantation and clinical pregnancy rates (PR). A total of 165 patients were enrolled in this study – 78 in the control group and 87 in the hCG-treated group. Progesterone levels and endometrial thickness were similar throughout the cycle in both groups. The E(2) level was significantly higher in group B on the day of embryo transfer and 6 days later. The PRs did not differ between the 2 groups (28.2% and 32.2% for groups A and B, respectively). Similarly, the implantation rates were comparable between the groups (12.7% and 14.9%, respectively). The authors concluded that no advantage was found concerning PR and implantation rate by supplementing the secretory phase with hCG in patients undergoing transfer of frozen-thawed embryo in hormonally modulated cycles.
In a systematic review and meta-analysis, Momeni et al. (2011) evaluated the relationship between endometrial thickness on the day of hCG administration and pregnancy outcome in in-vitro fertilization cycles. These investigators identified 484 articles using Cochrane library, PubMed, Web of Science, and Embase searches with various key words including endometrial thickness, pregnancy, assisted reproductive technology, endometrial pattern, and in-vitro fertilization. A total of 14 studies with data on endometrial thickness and outcome were selected, representing 4,922 cycles (2,204 pregnant and 2,718 non-pregnant). The meta-analysis with a random effects model was performed using comprehensive meta-analysis software. These researchers calculated the standardized mean difference (SMD), odds ratio (OR), and 95% confidence intervals (CIs). There was a significant difference in the mean endometrial thickness between pregnant and non-pregnant groups (p < 0.001), with a SMD of 0.4 mm (95% CI: 0.22 to 0.58). The OR for pregnancy was 1.40 (95% CI: 1.24 to 1.58). The authors concluded that the mean endometrial thickness was significantly higher in pregnant women compared to non-pregnant. The mean difference between 2 groups was less than 1 mm, which may not be clinically meaningful. Moreover, they stated that although there may be a relationship between endometrial thickness and pregnancy, implantation potential is probably more complex than a single ultrasound measurement can determine.
van der Linden et al. (2011) determined the relative safety and effectiveness of methods of luteal phase support in subfertile women undergoing assisted reproductive technology (ART). These investigators searched the Cochrane Menstrual Disorders and Subfertility Group (MDSG) Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO, CINAHL, Database of Abstracts of Reviews of Effects (DARE), LILACS, conference abstracts on the ISI Web of Knowledge, OpenSigle for grey literature from Europe, and ongoing clinical trials registered online. The final search was in February 2011. Randomized controlled trials of luteal phase support in ART investigating progesterone, hCG, or GnRH agonist supplementation in IVF or intra-cytoplasmic sperm injection (ICSI) cycles were included. Quasi-randomized trials and trials using frozen transfers or donor oocyte cycles were excluded. These researchers extracted data per woman, and three review authors independently assessed the risk of bias. They contacted the original authors when data were missing or the risk of bias was unclear, and they entered all data in six different comparisons. These investigators calculated the Peto odds ratio (Peto OR) for each comparison. A total of 69 studies with 16,327 women were included. The authors assessed most of the studies as having an unclear risk of bias, which we interpreted as a high risk of bias. Because of the great number of different comparisons, the average number of included studies in a single comparison was only 1.5 for live birth and 6.1 for clinical pregnancy. Five studies (746 women) compared hCG versus placebo or no treatment. There was no evidence of a difference between hCG and placebo or no treatment except for ongoing pregnancy: Peto OR 1.75 (95% CI: 1.09 to 2.81), suggesting a benefit from hCG. There was a significantly higher risk of ovarian hyper-stimulation syndrome (OHSS) when hCG was used (Peto OR 3.62, 95% CI: 1.85 to 7.06). There were eight studies (875 women) in the second comparison, progesterone versus placebo or no treatment. The results suggested a significant effect in favor of progesterone for the live birth rate (Peto OR 2.95, 95% CI: 1.02 to 8.56) based on one study. For clinical pregnancy (CPR), the results also suggested a significant result in favor of progesterone (Peto OR 1.83, 95% CI: 1.29 to 2.61) based on seven studies. For the other outcomes, the results indicated no difference in effect. The third comparison (15 studies, 2,117 women) investigated progesterone versus hCG regimens. The hCG regimens were subgrouped into comparisons of progesterone versus hCG and progesterone versus progesterone + hCG. The results did not indicate a difference of effect between the interventions, except for OHSS. Subgroup analysis of progesterone versus progesterone + hCG showed a significant benefit from progesterone (Peto OR 0.45, 95% CI: 0.26 to 0.79). The fourth comparison (9 studies, 1,571 women) compared progesterone versus progesterone + estrogen. Outcomes were subgrouped by route of administration. The results for clinical pregnancy rate in the subgroup progesterone versus progesterone + transdermal estrogen suggested a significant benefit from progesterone + estrogen. There was no evidence of a difference in effect for other outcomes. Six studies (1,646 women) investigated progesterone versus progesterone + GnRH agonist. These researchers subgrouped the studies for single-dose GnRH agonist and multiple-dose GnRH agonist. For the live birth, clinical pregnancy, and ongoing pregnancy rate, the results suggested a significant effect in favor of progesterone + GnRH agonist. The Peto OR for the live birth rate was 2.44 (95% CI: 1.62 to 3.67), for the clinical pregnancy rate was 1.36 (95% CI: 1.11 to 1.66), and for the ongoing pregnancy rate was 1.31 (95% CI: 1.03 to 1.67). The results for miscarriage and multiple pregnancies did not indicate a difference of effect. The last comparison (32 studies, 9,839 women) investigated different progesterone regimens: intra-muscular (IM) versus oral administration, IM versus vaginal or rectal administration, vaginal or rectal versus oral administration, low-dose vaginal versus high-dose vaginal progesterone administration, short protocol versus long protocol, and micronized progesterone versus synthetic progesterone. The main results of this comparison did not indicate a difference of effect except in some subgroup analyses. For the outcome clinical pregnancy, subgroup analysis of micronized progesterone versus synthetic progesterone showed a significant benefit from synthetic progesterone (Peto OR 0.79, 95% CI: 0.65 to 0.96). For the outcome multiple pregnancies, the subgroup analysis of IM progesterone versus oral progesterone suggested a significant benefit from oral progesterone (Peto OR 4.39, 95% CI: 1.28 to 15.01). The authors concluded that this review showed a significant effect in favor of progesterone for luteal phase support, favoring synthetic progesterone over micronized progesterone. Overall, the addition of other substances such as estrogen or hCG did not seem to improve outcomes. They also found no evidence favoring a specific route or duration of administration of progesterone. These investigators found that hCG, or hCG plus progesterone, was associated with a higher risk of OHSS. The use of hCG should therefore be avoided. There were significant results showing a benefit from the addition of GnRH agonist to progesterone for the outcomes of live birth, clinical pregnancy, and ongoing pregnancy. For now, progesterone seems to be the best option as luteal phase support, with better pregnancy results when synthetic progesterone is used.
Morley et al. (2013) stated that recurrent miscarriage (RM) is defined as the loss of 3 or more consecutive pregnancies. Further research is required to understand the causes of RM, which remain unknown for many couples. Human chorionic gonadotropin is vital for maintaining the corpus luteum, but may have additional roles during implantation which support its use as a therapeutic agent for RM. In a Cochrane review, these investigators determined the efficacy of hCG in preventing further miscarriage in women with a history of unexplained RM. They searched the Cochrane Pregnancy and Childbirth Group's Trials Register (September 30, 2012) and reference lists of retrieved studies. Randomized controlled trials investigating the efficacy of hCG versus placebo or no treatment in preventing RM were included for analysis. Quasi-randomized trials were included. Cluster-randomized trials and trials with a cross-over design were excluded. Two review authors independently assessed trials for inclusion and assessed the methodological quality of each study. Date were extracted by 2 review authors and checked for accuracy. These investigators included 5 studies (involving 596 women). Meta-analysis suggested a statistically significant reduction in miscarriage rate using hCG. The number of women needed to treat to prevent subsequent pregnancy loss was 7. However, when 2 studies of weaker methodological quality were removed, there was no longer a statistically significant benefit (risk ratio 0.74; 95% CI: 0.44 to 1.23). There were no documented adverse effects of using hCG. The authors concluded that the evidence supporting hCG supplementation to prevent RM remains equivocal. A well-designed randomized controlled trial of adequate power and methodological quality is required to determine whether hCG is beneficial in RM.
In a Cochrane review, Siristatidis et al. (2013) compared outcomes associated with in-vitro maturation (IVM) followed by IVF or ICSI versus conventional IVF or ICSI among women with PCOS undergoing assisted reproductive technologies (ART). They searched the Menstrual Disorders and Subfertility Group (MDSG) Specialised Register of controlled trials to May 2013 for any relevant trials identified from the title, abstract, or keyword sections. This was followed by a search of the electronic databases MEDLINE, EMBASE, LILACS, and CINAHL, without language restriction. They also performed a manual search of the references of all retrieved articles, sought unpublished papers and abstracts submitted to international conferences, searched the clinicaltrials.gov and WHO portal registries for submitted protocols of clinical trials, and contacted experts. In addition, these researchers examined the National Institute of Clinical Excellence (NICE) fertility assessment and treatment guidelines and hand-searched reference lists of relevant articles (from 1970 to May 2013). All randomized controlled trials (RCTs) on the intention to perform IVM before IVF or ICSI were compared with conventional IVF or ICSI for subfertile women with PCOS. Three review authors independently assessed eligibility and quality of trials. The primary outcome measure was live birth rate per randomized woman. There were no RCTs suitable for inclusion in the review, although there are currently three ongoing trials that have not yet reported results. The authors concluded that although promising data on the IVM technique have been published, unfortunately, there is still no evidence from RCTs upon which to base any practice recommendations regarding IVM before IVF or ICSI for women with PCOS.
In a Cochrane review, McDonnell et al. (2014) examined the effectiveness and safety of functional ovarian cyst aspiration prior to ovarian stimulation versus a conservative approach in women with an ovarian cyst who were undergoing IVF or ICSI. These investigators searched the Menstrual Disorders and Subfertility Group (MDSG) Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO, CINAHL, ClinicalTrials.gov, Google Scholar, and PubMed. The evidence was current to April 2014, and no language restrictions were applied. These researchers included all RCTs comparing functional ovarian cyst aspiration versus conservative management of ovarian cysts that had been seen on transvaginal ultrasound (TVS) prior to controlled ovarian hyperstimulation (COH) for IVF or ICSI. Ovarian cysts were defined as simple, functional ovarian cysts greater than 20 mm in diameter. Oocyte donors and women undergoing donor oocyte cycles were excluded. Study selection, data extraction, and risk of bias assessments were conducted independently by two review authors. The primary outcome measures were live birth rate and adverse events. The overall quality of the evidence for each comparison was rated using Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) Working Group methods. A total of three studies were eligible for inclusion (n = 339), all of which used agonist protocols. Neither live birth rate nor adverse events were reported by any of the included studies. There was no conclusive evidence of a difference between the group who underwent ovarian cyst aspiration and the conservatively managed group in the clinical pregnancy rate (OR 1.40, 95% CI: 0.67 to 2.94, three studies, 339 women, I² = 0%, low-quality evidence). This suggested that if the clinical pregnancy rate in women with conservative management was assumed to be 5%, the chance following cyst aspiration would be between 4% and 14%. There was no evidence of a difference between the groups in the mean number of follicles recruited (0.55 follicles, 95% CI: -0.48 to 1.59, two studies, 159 women, I² = 0%, low-quality evidence) or mean number of oocytes collected (0.41 oocytes, 95% CI: -0.04 to 0.85, three studies, 339 women, I² = 0%, low-quality evidence). Findings for the cancellation rate (two studies) were inconsistent, but neither study reported a benefit for the aspiration group. The main limitations of the evidence were imprecision, inconsistency, questionable applicability, and poor reporting of study methods. The authors concluded that there is insufficient evidence to determine whether drainage of functional ovarian cysts prior to controlled ovarian hyperstimulation influences live birth rate, clinical pregnancy rate, number of follicles recruited, or oocytes collected in women with a functional ovarian cyst. They stated that the findings of this review do not provide supportive evidence for this approach, particularly in view of the requirement for anesthesia, extra cost, psychological stress, and risk of surgical complications.
Genetic Testing in Assisted Reproductive Technologies
Gleicher et al. (2014) reviewed updated preimplantation genetic screening techniques (PGS#2) and concluded that these remain unproven and experimental due to the lack of well-designed, intent-to-treat trials. Lee et al. (2015) similarly concluded that while PGD-A may show benefit in young, good-prognosis patients, high-quality studies are needed to determine its overall clinical effectiveness.
Gleicher et al. (2014) noted that a few years ago, the ASRM, the European Society for Human Reproduction and Embryology (ESHRE), and the British Fertility Society declared preimplantation genetic screening (PGS#1) ineffective in improving IVF pregnancy rates and in reducing miscarriage rates. These investigators reviewed a presumably upgraded form of the procedure (PGS#2) that has recently been reintroduced. PGS#2, in comparison to PGS#1, is characterized by: (i) trophectoderm biopsy on day 5/6 embryos in place of day-3 embryo biopsy; and (ii) fluorescence in situ hybridization (FISH) of limited chromosome numbers is replaced by techniques allowing aneuploidy assessments of all 24 chromosome pairs. Reviewing the literature, the authors were unable to identify properly conducted prospective clinical trials in which IVF outcomes were assessed based on "intent-to-treat." Whether PGS#2 improves IVF outcomes can, therefore, not be determined. Reassessments of data alleged to support the effectiveness of PGS#2 indeed suggested the opposite. Like with PGS#1, the introduction of PGS#2 into unrestricted IVF practice again appears premature and threatens to repeat the PGS#1 experience, when thousands of women experienced reductions in IVF pregnancy chances while expecting improvements. The authors concluded that PGS#2 is an unproven and still experimental procedure, which, until evidence suggests otherwise, should only be offered under study conditions and with appropriate informed consent.
Lee et al. (2015) examined whether preimplantation genetic diagnosis for aneuploidy (PGD-A) with analysis of all chromosomes during ART is clinically and cost-effective. These investigators performed a systematic review of the literature for full-text English language articles using MEDLINE, EMBASE, SCOPUS, Cochrane Library databases, NHS Economic Evaluation Database, and EconLit. The Downs and Black scoring checklist was used to assess the quality of studies. Clinical effectiveness was measured in terms of pregnancy, live birth, and miscarriage rates. A total of 19 articles meeting the inclusion criteria, comprising 3 RCTs in young and good prognosis patients and 16 observational studies, were identified; 5 of the observational studies included a control group of patients where embryos were selected based on morphological criteria (matched cohort studies). Of the 5 studies that included a control group and reported implantation rates, 4 studies (including 2 RCTs) demonstrated improved implantation rates in the PGD-A group. Of the 8 studies that included a control group, 6 studies (including 2 RCTs) reported significantly higher pregnancy rates in the PGD-A group, and in the remaining 2 studies, equivalent pregnancy rates were reported despite fewer embryos being transferred in the PGD-A group. The 3 RCTs demonstrated benefits in young and good prognosis patients in terms of clinical pregnancy rates and the use of single embryo transfer. However, studies relating to patients of advanced maternal age, recurrent miscarriage, and implantation failure were restricted to matched cohort studies, limiting the ability to draw meaningful conclusions. The authors concluded that given the uncertain role of PGD-A techniques, high-quality experimental studies using intention-to-treat analysis and cumulative live birth rates, including the comparative outcomes from remaining cryopreserved embryos, are needed to evaluate the overall role of PGD-A in the clinical setting. It is only in this way that the true contribution of PGD-A to ART can be understood.
Cryopreservation
Guidelines from the Society for Reproductive Medicine and Society for Assisted Reproductive Technology (Pfeifer et al., 2013) recommend that oocyte cryopreservation with appropriate counseling is recommended in patients facing infertility due to chemotherapy or other gonOadotoxic therapies. The guidelines state that more widespread clinic-specific data on the safety and efficacy of oocyte cryopreservation in donor populations are needed before universal donor oocyte banking can be recommended. The guidelines state that there are not yet sufficient data to recommend oocyte cryopreservation for the sole purpose of circumventing reproductive aging in healthy women. The guidelines state that more data are needed before this technology should be used routinely in lieu of embryo cryopreservation.
Cryopreservation of immature oocytes and in vitro maturation are considered experimental procedures. The term in vitro maturation refers to the maturation in culture of immature oocytes after their recovery from follicles that may or may not have been exposed to exogenous FSH but were not exposed to either exogenous LH or hCG prior to retrieval to induce meiotic resumption. Guidelines from the American Society for Reproductive Medicine (2013) state that in vitro maturation should only be performed as an experimental procedure in specialized centers for carefully selected patients evaluating both efficacy and safety. The guidelines state that the initial results of in vitro maturation suggest the potential for clinical application. However, at this time, patients must be made aware that the implantation and pregnancy rates are significantly lower than with standard IVF, limiting more universal utilization.
Intracytoplasmic sperm injection (ICSI) has become standard of care for fertilization of frozen oocytes in in vitro cycles despite a lack of controlled studies (see, e.g., Kazem, et al., 1995; Gook, et al., 2005; Li, et al., 2005). Gook and Edgar (2007) explained that: "In contrast to the low normal fertilization rates observed in cryopreserved mouse oocytes, higher normal fertilization rates (∼50%) were observed following insemination of human oocytes cryopreserved using the DMSO [citing Al-Hasani et al., 1987; Siebzehnruebl et al., 1989; Hunter et al., 1991; Bernard et al., 1992] and the PROH procedures [citing Al-Hasani et al., 1987; Gook et al., 1994; Serafini et al., 1995]. Further evidence that cryopreservation using the PROH procedure had no adverse affect on fertilization was demonstrated by the observation of equivalent fertilization rates (∼50%) following insemination and ICSI [citing Gook et al., 1995; Li et al., 2005]. In contrast, Kazem et al. (1995) reported a lower rate with insemination (3%) relative to ICSI (43%). Despite the fact that there is no evidence from controlled comparisons of insemination techniques to suggest that ICSI is required to fertilize human cryopreserved oocytes, it has been adopted as the method of choice in subsequent clinical studies."
Embryo Transfers
To reduce multiple gestations and promote singleton pregnancies, the 2021 American Society for Reproductive Medicine and Society for Assisted Reproductive Technology (ASRM/SART) guidance provides age- and prognosis-based recommendations for embryo transfer in assisted reproductive technology (ART) cycles. Patients with a favorable prognosis (defined by factors such as young age, availability of high-quality or euploid embryos, prior live birth, and vitrified blastocysts) should receive fewer embryos:
- Transfer of a euploid embryo should be limited to one, regardless of patient age;
- Patients less than 35 years of age should be strongly encouraged to receive a single-embryo transfer, regardless of the embryo stage;
- Patients between 35 to 37 years of age, strong consideration should be made for a single-embryo transfer;
- Patients between 38 to 40 years of age, no more than 3 untested cleavage-stage embryos or 2 blastocysts should be transferred;
- Patients between 41 to 42 years of age should plan to receive no more than 4 untested cleavage-stage embryos or 3 blastocysts.
The ASRM/SART (2021) committee outlines other scenarios where deviation from standard embryo transfer limits may be considered: (i) patients in any age group with an unfavorable prognosis may receive an additional embryo, with counseling on the increased risk of multiple gestation; (ii) favorable prognosis patients who fail to conceive after multiple cycles with high-quality embryos may consider transferring an additional embryo; (iii) patients with medical conditions that could be worsened by multiple pregnancy should be limited to single embryo transfer; and (iv) in rare cases where embryo transfer exceeds recommended limits, both counseling and justification must be documented in the medical record. In women 43 years of age or older, there are insufficient data to recommend a limit on the number of embryos to transfer when the patient uses her own oocytes. Caution should be exercised as the risk associated with multiple pregnancy increases dramatically with advancing maternal age.
In donor-oocyte cycles, the donor’s age determines embryo transfer limits. If the donor is less than 38 years and other favorable criteria are met, single embryo transfer should be planned. In gestational carrier (GC) cycles, single embryo transfer is strongly recommended due to the health risks of multiple gestations. For frozen embryo transfer (FET) cycles, embryo transfer decisions should be on the basis of the age of the woman when the embryos were cryopreserved and include the presence of high-quality vitrified embryos, euploid embryos, first FET cycle, or previous live birth after a prior transfer with sibling embryo(s). Embryo transfer numbers should not exceed the recommended limit on the number of fresh embryos transferred for each age group.
Single-embryo transfer is strongly recommended in all gestational carrier (GC) cycles due to the significant health risks associated with multiple gestations for the carrier; at a minimum, embryo transfer should follow age-based limits determined by the age of the oocyte source (either the intended parent or donor). In frozen embryo transfer (FET) cycles, favorable prognostic factors include the age of the woman at the time of embryo cryopreservation, presence of high-quality vitrified or euploid embryos, undergoing a first FET cycle, or having had a prior live birth from sibling embryos. Regardless of these factors, the number of embryos transferred in FET cycles should not exceed the age-specific limits established for fresh embryo transfers.
Early Embryo Viability Assessment (Eeva) Test
In a prospective, multi-center cohort study, Conaghan et al. (2013) evaluated the first computer-automated platform for time-lapse image analysis and blastocyst prediction and determined how the screening information may assist embryologists in day 3 (D3) embryo selection. A total of 160 women aged 18 years or older undergoing fresh IVF treatment with a basal antral follicle count greater than or equal to 8, basal FSH less than 10 IU/ml, and greater than or equal to 8 normally fertilized oocytes were included in this study. A non-invasive test combining time-lapse image analysis with the cell-tracking software, Eeva (Early Embryo Viability Assessment), was used to measure early embryo development and generate usable blastocyst predictions by D3. The main outcome measure was the improvement in the ability of experienced embryologists to select which embryos are likely to develop into usable blastocysts using D3 morphology alone, compared with morphology plus Eeva. Experienced embryologists using Eeva in combination with D3 morphology significantly improved their ability to identify embryos that would reach the usable blastocyst stage (specificity for each of the three embryologists using morphology versus morphology plus Eeva: 59.7% versus 86.3%, 41.9% versus 84.0%, 79.5% versus 86.6%). Adjunctive use of morphology plus Eeva improved embryo selection by enabling embryologists to better discriminate which embryos would be unlikely to develop into blastocysts and was particularly beneficial for improving selection among good-morphology embryos. Adjunctive use of morphology plus Eeva also reduced inter-individual variability in embryo selection. The authors concluded that previous studies have shown improved implantation rates for blastocyst transfer compared with cleavage-stage transfer; the addition of Eeva to the current embryo grading process may improve the success rates of cleavage-stage ETs.
VerMilyea et al. (2014) noted that computer-automated time-lapse analysis has been shown to improve embryo selection by providing quantitative and objective information to supplement traditional morphology. In a blinded, multi-center study, these researchers examined the relationship between such computer-derived outputs (high, medium, low scores), embryo implantation, and clinical pregnancy. Data were collected from six clinics, including 205 patients whose embryos were imaged by the Eeva™ System. The Eeva scores were blinded and not considered during embryo selection. Embryos with high and medium scores had significantly higher implantation rates than those with low scores (37% and 35% versus 15%; p < 0.0001; p = 0.0004). Similar trends in implantation rates were observed in different IVF centers, each using their own protocols. Further analysis revealed that patients with at least one high embryo transferred had significantly higher clinical pregnancy rates than those with only low embryos transferred (51% versus 34%; p = 0.02), although patients' clinical characteristics across groups were comparable. The authors concluded that these data, together with previous research and clinical studies, confirmed that computer-automated Eeva scores provided valuable information, which may improve the clinical outcome of IVF procedures and ultimately facilitate the trend of single embryo selection.
In summary, there is currently insufficient evidence to support the use of the Eeva test for improving embryo selection.
DuoStim IVF Protocol
DuoStim IVF cycles are IVF cycles designed for women with a poor response to prior IVF cycles or diminished ovarian reserve. DuoStim consists of two steps. Step one includes stimulation, aspiration, fertilization, and freezing of the embryos. Step two occurs after aspiration in step one and involves the stimulation of any follicles that were too small to aspirate in step one. This second crop of follicles undergoes aspiration and fertilization.
Massin (2017) noted that the advent of embryo and oocyte vitrification today gives reproductive specialists an opportunity to consider new strategies for improving the practice and results of in-vitro fertilization (IVF) attempts. As the freezing of entire cohorts does not compromise, and may even improve, the results of IVF attempts, it is possible to break away from the standard sequence of stimulation-retrieval-transfer. The constraints associated with ovarian stimulation in relation to the potential harmful effects of the hormonal environment on endometrial receptivity can be avoided. This review examined the new stimulation protocols where progesterone is used to block the LH surge. Thanks to "freeze all" strategies, the increase in progesterone could actually be no longer a cause for concern. There are two ways of using progesterone, whether it be endogenous, as in luteal phase stimulation, or exogenous, as in the use of progesterone in the follicular phase, i.e., progestin-primed ovarian stimulation. These investigators performed a literature search (until September 2016) on Medline. The following text words were utilized to generate the list of citations: progestin-primed ovarian stimulation, luteal phase stimulation, luteal stimulation, DuoStim, double stimulation, and random start. Articles and their references were then examined in order to identify other potential studies. All of the articles were reported in this review. The use of progesterone during ovarian stimulation is effective in blocking the LH surge, whether endogenous or exogenous, and it does not affect the number of oocytes collected or the quality of the embryos obtained. Its main constraint is that it requires total freezing and delayed transfer. A variety of stimulation protocols can be derived from these two methods, and their implications were discussed, from fertility preservation to ovarian response profiles to organization for the patients and clinics. These new regimens enable more flexibility and are of emerging interest in daily practice. However, their medical and economic significance remains to be demonstrated. The authors concluded that the use of luteal phase or follicular phase protocols with progestins could rapidly develop in the context of oocyte donation and fertility preservation not related to oncology. Their place could develop even more in the general population of patients in IVF programs. The strategy of total freezing continues to develop, thanks to technical improvements, in particular vitrification and PGS on blastocysts, and thanks to studies showing improvements in embryo implantation when the transfer takes place far removed from the hormonal changes caused by ovarian stimulation.
Vaiarelli et al. (2018) stated that the management and treatment of patients with poor ovarian response is still a controversial issue in IVF. Increasing evidence demonstrates that the number of oocytes retrieved after a controlled ovarian stimulation (COS) greatly influences the clinical outcome in terms of cumulative live birth per started cycle. For this reason, any COS should aim to optimize the number of oocytes according to the ovarian reserve of the patient. These investigators provided an overview of new strategies proposed to manage poor responders according to the novel POSEIDON classification. Gonadotrophins cannot compensate for the absence of follicles in the ovary; therefore, COS in poor responders may benefit from the exploitation of multiple follicular waves within a single ovarian cycle, for instance, through luteal phase stimulation or double stimulation (follicular plus luteal) in the same ovarian cycle (DuoStim) protocols. The authors concluded that many strategies have been proposed to manage poor responder patients; however, a consensus on which is the most beneficial has not yet been reached. DuoStim is the most promising approach to increase the number of oocytes collected in a single ovarian cycle; however, more embryological and clinical data are needed, as well as an analysis of its cost-effectiveness.
Cimadomo et al. (2018) noted that three theories of follicle recruitment have been postulated to date: the “continuous recruitment” theory, the “single recruitment episode” theory, and the “wave” theory. Yet, a clear characterization of this crucial biological process for human reproduction is missing. Recent advances implemented in IVF, such as blastocyst culture, aneuploidy testing, and vitrification, have encouraged clinicians to maximize the exploitation of the ovarian reserve through tailored stimulation protocols, which is crucial, especially for poor prognosis patients aiming to conceive after IVF. Luteal phase stimulations (LPS) have already been successfully adopted to treat poor prognosis or oncological patients through DuoStim, LPS-only, or random-start ovarian stimulation approaches. Nevertheless, little, and mainly retrospective, evidence has been produced to support the safety of LPS in general. The feasibility of the LPS approach would severely question the classic “single recruitment episode” theory of follicular development. In a case-control study, these researchers determined if the mean numbers of blastocysts obtained from sibling cohorts of oocytes recruited after follicular phase stimulation (FPS) and LPS in the same ovarian cycle are similar. This trial was carried out with paired follicular phase- and luteal phase-derived cohorts of oocytes collected after stimulations in the same ovarian cycle (DuoStim) at two private IVF clinics between October 2015 and December 2017. This study included 188 poor prognosis patients undergoing DuoStim with pre-implantation genetic testing for aneuploidies (PGT-A); FPS and LPS were performed with the same daily dose of recombinant gonadotrophins in an antagonist protocol. Blastocyst culture, trophectoderm biopsy, vitrification, and frozen-warmed euploid single blastocyst transfers were performed. The primary outcome was the mean number of blastocysts obtained per oocyte retrieval from paired FPS- and LPS-derived cohorts (required sample size = 165 patients; power = 90%). Mean blastulation and euploidy rates were monitored, along with the number of oocytes, euploid blastocysts, and clinical outcomes. Significantly fewer blastocysts were obtained after FPS than LPS (1.2 ± 1.1 versus 1.6 ± 1.6, p < 0.01), due to fewer oocytes collected (3.6 ± 2.1 versus 4.3 ± 2.8, p < 0.01) and a similar mean blastocyst rate per retrieval (33.1% ± 30.3% versus 37.4% ± 30.8%, p = NS). The number of oocytes collected was correlated (R = 0.5, p < 0.01), while the blastocyst rates were uncorrelated among paired FPS- and LPS-derived cohorts. Overall, a significantly lower chance of producing blastocyst(s) was reported after FPS than after LPS: 67.6% (n = 127/188, 95% confidence interval [CI]: 60.3 to 74.1) versus 77.1% (n = 145/188, 95% CI: 70.3 to 82.8; p = 0.05). The mean euploidy rates per retrieval were similar between FPS- and LPS-derived cohorts of oocytes (13.6% ± 22.8% versus 16.3% ± 23.4%, p = NS). Thus, on average, fewer euploid blastocysts (0.5 ± 0.8 versus 0.7 ± 1.0, p = 0.02) resulted from FPS. Similar ongoing pregnancy/delivery rates were reported to date after FPS- and LPS-derived euploid single blastocyst transfers: 42.4% (n = 28/66, 95% CI: 30.5 to 55.2) versus 53.8% (n = 35/65, 95% CI: 41.1 to 66.1; p = NS). The authors concluded that this study provided evidence that the follicles recruited during the anovulatory phase of the ovarian cycle may be rescued through LPS. Of note, LPS-derived cohorts of oocytes were also larger than paired FPS-derived cohorts, and the oocytes showed comparable competence. These data supported the putative benefits of LPS in poor prognosis and oncological patients. Furthermore, they encourage additional clinical and basic research studies on this topic, which may revolutionize the basics of human folliculogenesis, as well as the future concept of approaches to ovarian stimulation in IVF.
The authors stated that more studies need to be conducted in the future to confirm the safety of LPS, especially in terms of the ovarian and follicular environment, as well as the clinical, perinatal, and postnatal outcomes. The findings of this study showed preliminary data suggesting a similar ongoing implantation/delivery rate (greater than 22 weeks) between FPS- and LPS-derived euploid blastocysts that need to be extended in the future to populations other than poor prognosis patients and using approaches other than DuoStim, together with constant monitoring of the related perinatal and postnatal outcomes.
- a RCT comparing double-FPS versus DuoStim;
- the application of DuoStim in cancer patients for fertility preservation;
- as well as in prospective analyses focused on patients clustered according to either the Bologna criteria or the Poseidon stratification.
They stated that until such evidence would be produced, DuoStim should be clinically applied only to a population of patients of poor prognosis and/or to whom time represents a critical issue.
The authors stated that the weaknesses of DuoStim are: a higher number of stimulations appeared to be canceled in the LP than in the FP; no RCT or cost-effectiveness analysis has been performed to-date investigating the use of DuoStim; a freeze-all approach is mandatory; it has been applied only to poor prognosis patients. The opportunities are: a decrease in the time and increase in the chance to obtain at least 1 competent embryo in a single menstrual cycle; the DuoStim protocol might be better-tolerated from the patients than consecutive FPS cycles; the drop-out rate might be reduced; the knowledge regarding the mechanisms of follicular recruitment and ovarian physiology might be increased. The threats are: an analysis of the cost-effectiveness is yet eagerly needed; the total dose of gonadotrophins to be administrated is substantial; few biological, gynecological, obstetrical, and neonatal evidence of safety have been produced to date. The strengths of this approach make it very promising. However, more studies are needed in the future to limit its weaknesses, shed light on its putative threats, and realize its opportunities.
There is a clinical trial on “DuoStim in Cases of PGT: Comparison of Embryo Quantity and Embryonic Quality Using MitoScore” that is currently recruiting participants (last updated September 3, 2018).
Endometrial Receptivity Analysis (Igenomix)
The Endometrial Receptivity Analysis (ERA; Igenomix) is a test designed to evaluate endometrial receptivity. It is the first diagnostic test that determines each woman’s unique personalized embryo transfer (ET) timing, thus synchronizing the ET with the individualized window of implantation. The ERA uses RNA obtained from an endometrial tissue sample. The RNA is analyzed and then classified by Igenomix’s ERA predictor as receptive or non-receptive, depending on the expression profile of the RNA. The ERA test couples next-generation sequencing (NGS) to a computational predictor to identify transcriptomic signatures for each endometrial stage: proliferative (PRO), pre-receptive (PRE), receptive (R), and post-receptive (POST). If the endometrium is non-receptive, the test enables clinicians to find a personalized window of implantation for each patient in the majority of cases.
In an open-label, multi-center randomized controlled trial (RCT), Simon and colleagues (2020) examined whether the clinical performance of personalized ET (PET) guided by ERA would differ from frozen ET (FET) or fresh ET in infertile patients undergoing IVF. This trial included 458 patients aged 37 years or younger undergoing IVF with blastocyst transfer at their first appointment; they were randomized to PET guided by ERA, FET, or fresh ET in 16 reproductive clinics. Clinical outcomes by intention-to-treat (ITT) analysis were comparable, but the cumulative pregnancy rate (CPR) was significantly higher in the PET group (93.6%) compared with the FET group (79.7%) (p = 0.0005) and the fresh ET group (80.7%) (p = 0.0013). Analysis per protocol demonstrated that live birth rates (LBRs) at the first ET were 56.2% in the PET group versus 42.4% in the FET group (p = 0.09) and 45.7% in the fresh ET group (p = 0.17). Cumulative LBRs (CLBRs) after 12 months were 71.2% in the PET group versus 55.4% in the FET group (p = 0.04) and 48.9% in the fresh ET group (p = 0.003). Pregnancy rates at the first ET in the PET, FET, and fresh ET arms were 72.5% versus 54.3% (p = 0.01) and 58.5% (p = 0.05), respectively. Implantation rates at the first ET were 57.3% versus 43.2% (p = 0.03) and 38.6% (p = 0.004), respectively. Obstetrical outcomes, type of delivery, and neonatal outcomes were similar in all groups. The authors concluded that, to the best of their knowledge, this was the first RCT aiming to provide proof-of-principle evidence for the potential of using a personalized diagnosis of the endometrial factor in the work-up of the infertile couple at the first appointment. While the ITT analysis showed no beneficial effect of the ERA test except for a statistically significant CPR compared with FET and fresh ET, the per-protocol analysis demonstrated a significant improvement in pregnancy rates at the first attempt and cumulative rates up to 12 months, as well as implantation rates at the first attempt, indicating the potential of the ERA test to diagnose the endometrial factor in the work-up of the infertile couple. Moreover, these researchers stated that these findings need to be confirmed in a larger randomized clinical trial.
The authors stated that the main drawback of this study was the unexpected 50% patient drop-out rate versus the 30% initially planned. This situation has rendered the study underpowered to detect statistical significance by ITT analysis in the PET arm versus FET and fresh ET, except for higher CLBR. This sample size affected the per-protocol analysis; although the analysis detected a 13.8 and 10.5 percentage point increase in LBR in the PET group versus FET and fresh ET at the first ET, the difference was not significant because the study was powered to detect statistical differences for a 15 percentage point increase in the primary and secondary outcomes. Second, in the historical setting in which this RCT was designed, ERA was performed using microarray technology with early algorithms, and in some cases, two endometrial biopsies were needed for diagnosis. At the time of publication, ERA is being carried out by NGS combined with refined algorithms informed by the analysis and clinical follow-up of more than 50,000 endometrial samples worldwide; additionally, only one endometrial biopsy is needed. Because of the indicated constraints of the study, these researchers are performing a new ERA 2.0 RCT, in which the current sequencing technology and refined algorithms will be included together with proper power for the study.
In a prospective cohort study, Riestenberg and associates (2021) compared the LBR between patients who underwent personalized ET (pET) after ERA versus FET with standard timing in their first single euploid FET cycles. These researchers also reported the rate of displacement of the window of implantation (WOI) in an infertile population without a history of implantation failure. Subjects were patients who underwent their first single euploid programmed FET; they underwent their first autologous single euploid programmed FET between January 2018 and April 2019. Subjects underwent endometrial biopsy with ERA followed by pET as indicated. Main outcome measures included LBR as well as the rate of receptive and non-receptive ERA. A total of 228 single euploid FET cycles were included in this analysis. Of those, 147 (64.5%) were ERA/pET cycles, and 81 (35.5%) were standard timing FET cycles. The endometrial receptivity array was receptive in 60/147 (40.8%) and non-receptive in 87/147 (59.2%) patients. Non-receptive ERAs were pre-receptive in 93.1% of cases. The LBR did not differ between patients who underwent FET with standard timing and patients who underwent ERA/pET, 45/81 (56.6%) and 83/147 (56.5%), respectively. The authors concluded that the findings of this study did not support the routine use of ERA in an unselected patient population undergoing their first autologous single euploid programmed ET.
In a retrospective cohort study, Bergin and co-workers (2021) examined the impact of the ERA on LBRs in FET cycles. Autologous FET cycles between January 1, 2014, and June 30, 2019, were reviewed. Multiple covariates that impacted outcomes were used for propensity score matching; 133 ERA patients were matched to 353 non-ERA patients. Patients were assigned to the ERA group if they had an ERA during treatment and underwent at least one "personalized" FET (pFET) based on the ERA recommendations. Main outcome measures included LBRs per cycle in the FET cycle after ERA compared with that of matched non-ERA patients. The LBRs for the ERA group were 49.62%, and for the matched non-ERA group, 54.96% (OR 0.8074; 95% CI: 0.5424 to 1.2018) were not significantly different, nor was a difference observed in sub-analyses based on the prior number of FETs or receptivity status. The authors concluded that ERA identified a patient's putative WOI with the objective of improving synchrony with the embryo, thus attaining higher LBRs. This study used propensity score matching to control for multiple covariates in a heterogeneous group of patients to compare LBRs. There was no difference in the LBRs in patients who underwent ERA compared with those who did not.
In a retrospective study, Eisman and associates (2021) examined the use of the ERA in women with prior failed ET. This trial included patients who underwent an ERA test with a subsequent FET. Women were classified based on their indication for an ERA test: greater than or equal to one prior failed ET (cases) or as a prophylactic measure (controls). A subset analysis of women with greater than or equal to three prior failed ETs was carried out. Pregnancy outcomes of the subsequent cycle were examined, including conception, clinical pregnancy, and ongoing pregnancy/live birth. A total of 222 women were included, with 131 (59%) women having greater than or equal to one prior failed ET and 91 (41%) controls. Among the 131 women with greater than or equal to one prior failed ET, 20 women (9%) had greater than or equal to three prior failed ETs. The proportion of non-receptive ERA tests in the three groups were as follows: 45% (greater than or equal to one prior failed ET), 40% (greater than or equal to three prior failed ETs), and 52% (controls). The results did not differ between cases and controls. The pregnancy outcomes did not differ between women with greater than or equal to one prior failed ET and controls. In women with greater than or equal to three prior failed ETs, there was a lower ongoing pregnancy/LBR (28% versus 54%, p = 0.046). The authors concluded that women with greater than or equal to one prior failed ET and greater than or equal to three prior failed ETs had a similar prevalence of non-receptive endometrium compared to controls. Women with greater than or equal to three prior failed ETs had a lower ongoing pregnancy/LBR despite a personalized FET, suggesting that there are additional factors in implantation failure beyond an adjustment in progesterone exposure.
Rafeal (2021) discussed the limitations of the ERA methodology to increase implantation. Such limitations varied from the assumed inconsistency of the endometrial biopsy, the variable number of genes found to be dysregulated in endometrial samples without the embryonal-induced effect, the failure to account for the simultaneous serum progesterone level, and the expected low percentage of patients who may need this add-on procedure, to the difficulties in synchronizing the endometrium with hormone replacements in successive cycles and the inherent perinatal risks associated with routine cryopreservation of embryos. Without a gold standard to compare, the claim that the WOI might be off by ± 12 hours only requires a good argument for the advantage it provides to human procreation, knowing that embryos can linger for days before actual embedding starts and that the window is actually a few days. Moreover, the intra-patient variations in the test need to be addressed. The author stated that clinicians tend to grasp any new idea that could potentially improve results, also to demonstrate that they are competitive and updated; however, even after many years of practice, most add-ons have been deemed not proven. New tests, such as the ERA, until shaped and proven, should be offered only under research protocols that separate compounding factors, considering all the reservations, and keeping in mind that freezing embryos is not risk-free. As witnessed before, a single RCT or even a meta-analysis should not be accepted as final proof of its overall utility as a new solution or its widespread use. It is the duty of clinical societies and peer-reviewed journals to follow up on the evidence and filter new ideas and technological procedures to avert physicians from repeating false directions or mistakes for longer than necessary. The author concluded that, like all other add-ons, it is doubtful that the ERA test would significantly enhance implantation success rates.
Evaluation of Telomere Length for Female and Male Infertility
Vasilopoulos and colleagues (2019) noted that telomere length (TL) has long been associated with aging, as telomeres serve as protective caps of chromosomes, and are thus deeply involved in the preservation of genome integrity and are vital to cellular functions. Traditionally, a strong link connects aging and infertility in both sexes, with an earlier onset in females. Over the last 10 years, telomeres have attracted increasing attention due to the role they play in fertility. In this review, these investigators examined the potential positive or negative association between relative TL and different factors of female and male infertility. They carried out a systematic search of the PubMed database. A total of 206 studies were identified; 45 met the criteria of validity and relevance. Following an analysis and a comparison of the study outcomes, several clear trends were observed. The majority of female infertility factors were associated with a shorter TL, with the exception of endometriosis, premature ovarian failure and clear cell carcinoma that were associated with a longer TL and PCOS, which revealed conflicting results among several studies, leading to ambiguous conclusions. Male infertility factors were associated with a shorter TL. The authors concluded that although the findings of this review could provide an outline of general trends in the association of TL with infertility factors, further epidemiological and original research studies are needed to examine the basis of these varying lengths of telomeres. Moreover, these researchers stated that many questions must first be addressed before the use of TL as a marker for identification of reproductive capacity can be employed in a clinical setting. They stated that further studies are needed to understand the bases of TL associations with biological aging and reproductive capacity, and to determine how this knowledge can be used in medical applications.
Evaluation of Vaginal Microbiota
In a systematic review and meta-analysis, Hong and colleagues (2020) examined the association between vaginal microbiota and infertility. These investigators searched a range of electronic databases for appropriate articles, including PubMed, Web of Science, Embase, Chinese National Knowledge Infrastructure (CNKI), and Wanfang, from inception to September 8, 2019. Identified articles were then screened using strict inclusion and exclusion criteria. By referring to Tamarelle's method, these researchers divided vaginal microbiota into 2 categories: low-Lactobacillus vaginal microbiota (LL-VMB) and high-Lactobacillus vaginal microbiota (HL-VMB). Patients were defined as HL-VMB if they had a Nugent score of 0 to 3, a negative Amesel/Spiegel's test, or if the vaginal community status was dominated by either L. crispatus, L. iners, L. gasseri and L. jensenii via 16S rRNA sequencing. Otherwise, cases were regarded as LL-VMB. Statistical analyses were carried out with STATA 13.0 statistical software. Effect estimates are presented as ORs with 95% CIs. A total of 15 articles were included in the final analysis. The HL-VMB was negatively related to infertility; a fixed model showed that the pooled OR was 0.83 (95% CI: 0.77 to 0.90). There was no significant publication bias, as determined by Begg's test (p = 0.488) and Egger's test (p = 0.652). Using a random effect model, the pooled OR for intermediate bacterial vaginitis (BV) and infertility was 1.39 (95% CI: 1.10 to 1.76) and the pooled OR for positive BV was 1.72 (95% CI: 1.10 to 2.69). Subgroup and sensitivity analyses further demonstrated that the associations identified were stable; however, the acquired evidence was insufficient to make inferences with regards to the mechanisms underlying these relationships. The authors concluded that this systematic review and meta-analysis identified a negative correlation between HL-VMB and female infertility. However, due to a variety of limitations, the evidence acquired did not allow these researchers to identify the specific mechanisms underlying this association. They stated that further high-quality studies are needed to verify the causal relationship and examine the molecular mechanisms involved.
Hyperbaric Oxygen Therapy
Metelev et al. (2015) examined the potential of hyperbaric oxygen (HBO) for reduction of sperm DNA fragmentation level and reactive oxygen species (ROS) in semen. The study included 90 men with idiopathic infertility. Patients of the treatment group (n = 60) underwent HBO before IVF. In the control group (n = 30) IVF was carried out without prior course of HBO. Sperm DNA fragmentation analysis was carried out using the TUNEL assay, the level of ROS in the ejaculate was measured by chemiluminescence. Hyperbaric oxygen therapy resulted in a significant decrease in the mean level of sperm DNA fragmentation from 33.2 ± 7.5 to 11.9 ± 5.9%, and the median ROS in sperm from 0.89 to 0.39 mV/s (p < 0.05). In the control group these changes were not statistically significant. Pregnancy after IVF occurred in 63.3% (38/60) of sexual partners of the treatment group men and in 36.7% (11/30) of the control group (p < 0.05). The authors concluded that the high efficiency of HBO in overcoming the adverse effects of oxidative stress on sperm parameters suggested that it is a promising method for the treatment of men with idiopathic infertility.
Hysterosalpingo-Foam Sonography (HyFoSy)
Hysterosalpingogram (HSG), which uses dye, fluoroscopy and x-ray techniques, is the standard of care test used for evaluation of tubal patency due to its therapeutic and diagnostic benefits. Hysterosalpingo-contrast sonography (HyCoSy), which uses ultrasound and microbubble or agitated saline contrast, is considered a reasonable alternative (Kuohung and Hornstein, 2024).
Transvaginal hysterosalpingo-foam sonography (HyFoSy) is a novel ultrasound method that uses intrauterine foam contrast (e.g., ExEm Foam) to evaluate the patency of the fallopian tubes in women who are having difficulty getting pregnant.
ExEm Foam (ExEm Inc.) is an FDA-approved ultrasound contrast agent indicated for sonohysterosalpingography to assess fallopian tube patency in women with known or suspected infertility. ExEm Foam is a reconstituted air polymer-type A foam that is infused via a catheter that is inserted into the cervix. The foam creates an echogenic effect in the fallopian tubes and peritoneal cavity which can be visualized with transvaginal ultrasound.
In a randomized controlled trial, Dreyer et al. (2014) evaluated whether HyFoSy is a less painful first-line tubal patency test than serial HSG. The trial included 40 subfertile women, ages 18 to 41 years, with an indication for tubal patency testing as part of the fertility workup according to the Dutch Nederlandse Vereniging voor Obsteterie & Gynaecologie guidelines. The women were randomized to either HyFoSy or serial HSG. Visual Analogue Scale (VAS) pain scores were used during tubal patency testing. The authors found that the median VAS score for pain perception during the HyFoSy procedure was 1.7 cm (interquartile range: 2.1) compared with 3.7 cm (interquartile range: 4.2) during HSG. The HyFoSy procedure also had a statistically significantly shorter procedure time compared with HSG, with a median of 5.0 minutes (interquartile range: 3.0) for HyFoSy versus 12.5 minutes (interquartile range: 16.0) for HSG. The authors concluded that the HyFoSy procedure is a less painful and less time-consuming tubal patency test compared with HSG.
In a prospective observational study, Ludwin et al. (2017) reviewed the accuracy of HyFoSy in comparison to HyCoSy with air/saline and to laparoscopy with dye in 132 infertile women consecutively enrolled in the study from 2013 to 2015. 2D-Air/saline-HyCoSy, 2D/3D-HyFoSy, and 2D/3D-HDF-HyFoSy and laparoscopy were performed independently. The authors found that 2D-Air/saline-HyCoSy, 2D/3D-HyFoSy, and 2D/3D-HDF-HyFoSy indicated that 46 (17.8%), 27 (10.4%), and 24 (9.2%) of the 259 tubes were occluded, respectively; additionally, inconclusive results were obtained for 8 (3%), 5 (1.9%), and 3 (1.2%) tubes, respectively. The reference method revealed 18 (6.9%) occluded Fallopian tubes. 2D-Air/saline-HyCoSy had a high negative predictive value (NPV) (99.5%) that was similar to that of 2D/3D-HyFoSy (99%) and 2D/3D-HDF-HyFoSy (99.6%) (P > 0.05), but had a very low positive predictive value (PPV) (30.4%). The use of 2D/3D-HyFoSy, especially 2D/3D-HDF-HyFoSy, which had a significantly higher PPV (48% and 71%, P < 0.05 and P < 0.01, respectively), resulted in fewer false positive and inconclusive findings than the use of 2D-Air/saline-HyCoSy. The LR- and LR+ were 0.14 and 14.8, respectively, for 2D/3D-HyFoSy, 0.06 and 32.1, respectively, for 2D/3D-HDF-HyFoSy, and 0.08 and 6.9, respectively, for 2D-Air/saline-HyCoSy. The number of inconclusive or positive results per patient was significantly fewer with 2D/3D-HyFoSy (odds ratio, OR = 0.5, CI = 0.3-0.95, P < 0.05) and 2D/3D-HDF-HyFoSy (OR = 0.4, 95% CI = 0.2-0.8, P < 0.01) than with 2D-Air/saline-HyCoSy. The authors acknowledged limitations to their study. An unselected infertile population with a low prevalence of tubal occlusion is suitable for estimating the diagnostic accuracy of imaging tests only as a screening tool. The authors concluded that 2D-Air/saline-HyCoSy, which has a high NPV, is suitable as an initial test and basic screening method, but 2D/3D-HDF-HyFoSy, which has a significantly higher PPV, can be used as a standard to verify any questionable or positive results obtained with 2D HyCoSy. This strategy may significantly reduce the need for laparoscopy as a reference standard.
In a prospective randomized study, Piccioni et al. (2017) compared sonohysterosalpingography (sono-HSG) with foam instillation (HyFoSy) versus saline solution (HyCoSy) in the evaluation of tubal patency in 37 infertile women. The women were randomized into two groups: HyFoSy (group I) and HyCoSy (group II). The patients of both groups underwent laparoscopy with a dye test. The authors assessed the diagnostic performance (sensitivity, specificity, and overall accuracy) of HyFoSy and HyCoSy compared with laparoscopy and dye test in the assessment of tubal patency. The authors found that sono-HSG findings in tubal patency assessment obtained in the HyFoSy group were concordant with laparoscopic results in 94.4% of cases, with a sensitivity of 87.5% and a specificity of 100%, whereas in the HyCoSy group, concordance occurred in only 57.8% of examinations, with a sensitivity of 50% and a specificity of 66.6%. The authors concluded that HyFoSy allows for a more accurate diagnosis of tubal patency compared with HyCoSy; however, limitations in this study include a small sample size.
In a pilot study, Riganelli et al. (2018) aimed to compare 2D and 3D sonohysterosalpingography (2D-3D-HyFoSy) with previous diagnostic laparoscopy in the diagnosis of tubal patency and compare each procedure in terms of procedure time, perceived pain, and complication rate. The authors prospectively recruited 50 infertile women, previously submitted to laparoscopy, and randomly allocated them into 2D-HyFoSy (group I; n=25) and 3D-HyFoSy (group II; n=25). They analyzed the results in terms of sensitivity, specificity, positive predictive value, and negative predictive value in tubal patency evaluation of both procedures in comparison with laparoscopy. The authors stated that 2D-HyFoSy findings obtained in group I were concordant with laparoscopy in 81% of cases, with a sensitivity of 80% and a specificity of 92%. In group II, a correspondence was present in 88% of examinations, with a sensitivity and specificity of 98% and 91.4%, respectively. 3D-HyFoSy was found to be faster and less painful than 2D (P < 0.001). The authors concluded that in the diagnosis of tubal occlusion in a high-risk population, it seems advisable to use 3D-HyFoSy as the first-level examination, while in low-risk patients, if the tubes appear obstructed in 2D-HyFoSy, the 3D-HyFoSy should be indicated before submitting patients to operative laparoscopy.
An expert panel on women's imaging discussed the 2020 American College of Radiology (ACR) appropriateness criteria in female infertility. The authors state that "Hysterosalpingo-foam sonography in combination with 2-D or 3-D imaging has demonstrated improved accuracy of 93.7% and better concordance with laparoscopy compared with 2-D or 3-D air or saline HyCoSy for assessment of tubal patency. The addition of high-definition flow (bidirectional Doppler feature) achieved even higher accuracy at 96.9%, comparable with the reference method of laparoscopic chromopertubation with dye. However, high-definition flow still needs to be validated by other groups." However, the citations used for support included Ludwin et al. (2017), a prospective observational study comparing HyFoSy and HyCoSy in 132 women, and Piccioni et al. (2017), a prospective randomized study comparing foam and saline in 37 infertile women.
In a multicenter, prospective, randomized, non-inferiority study, van Welie et al. (2022) evaluated whether HyFoSy could replace HSG as a first-choice tubal patency test. The study included infertile women between 18 and 41 years old who were scheduled for tubal patency testing during their fertility workup in the Netherlands. Women with anovulatory cycles not responding to ovulation induction, endometriosis, severe male infertility, or a known iodine contrast allergy were excluded. The primary outcome for the comparison of the HyFoSy- and HSG-based strategies was ongoing pregnancy leading to live birth within 12 months after inclusion in an intention-to-treat analysis. Participating women underwent both HyFoSy and HSG in randomized order. In case of discordant results, women were randomly allocated to either a management strategy based on HyFoSy or one based on HSG. Between May 2015 and January 2019, 1,026 women underwent HyFoSy and HSG. HyFoSy was inconclusive in 97 of them (9.5%), HSG was inconclusive in 30 (2.9%), and both were inconclusive in 9 (0.9%). In 747 women (73%), conclusive test results were concordant. Of the 143/1,026 (14%) with discordant results, 105 were randomized to clinical management based on the results of either HyFoSy or HSG. In this group, 22 of the 54 women (41%) allocated to management based on HyFoSy and 25 of 51 women (49%) allocated to management based on HSG had an ongoing pregnancy leading to live birth (Difference -8%; 95% CI: -27% to 10%). In total, clinical management based on the results of HyFoSy was estimated to lead to a live birth in 474 of 1,026 women (46%) versus 486 of 1,026 (47%) for management based on HSG (Difference -1.2%; 95% CI: -3.4% to 1.5%). Given the predefined margin of -2%, statistically significant non-inferiority of HyFoSy relative to HSG could not be demonstrated (P = 0.27). The mean pain score for HyFoSy on the 1-10 Visual Analogue Scale (VAS) was 3.1 (SD 2.2), and the mean VAS pain score for HSG was 5.4 (SD 2.5; P for difference < 0.001). The authors acknowledged limitations in the study. Since all women underwent both tubal patency tests, no conclusions on a direct therapeutic effect of tubal flushing could be drawn. A majority of the women (85%) had a low risk for tubal pathology. The authors concluded that HyFoSy and HSG produce similar tubal pathology findings in a majority of infertile couples, and where they differ, a difference in findings does not lead to a substantial difference in pregnancy outcome, while HyFoSy is associated with significantly less pain. However, before final conclusions on clinical management can be drawn, a head-to-head comparison between HyFoSy and HSG with oil-based contrast may be needed.
Intralipid Infusion for the Treatment of Female Infertility
In a double-blind, randomized controlled trial (RCT), Dakhly et al. (2016) examined the efficacy of intralipid supplementation in women with recurrent spontaneous abortion (RSA) and elevated natural killer (NK) cell activity undergoing in-vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). This study was conducted between February 10, 2013, and April 30, 2015, at a center in Egypt. Women with unexplained secondary infertility, RSA, and elevated levels of NK cells (greater than 12%) were enrolled and randomly assigned to receive either intralipid (2-ml diluted at 20% in 250 ml saline) or saline (250 ml) infusion on the day of oocyte retrieval using random numbers and sealed envelopes. Patients and attending physicians were masked to group assignment. The infusions were repeated within one week of a positive pregnancy test and then every two weeks until the end of the first trimester. The primary outcome was chemical pregnancy 14 days after embryo transfer. Analyses were performed by intention-to-treat (ITT). A total of 296 women were enrolled. Chemical pregnancy was recorded for 84 (58.3%) of 144 women in the intralipid group and 76 (50.0%) of 152 in the control group (p = 0.129). The authors concluded that intralipid supplementation did not increase the frequency of chemical pregnancy; however, findings related to ongoing pregnancy and live birth should be further examined.
In a systematic review and meta-analysis, Achilli et al. (2018) examined the evidence on the role of immunotherapy in IVF and in the management of recurrent pregnancy loss (RPL). These researchers conducted a literature search using Medline, PubMed, CINAHL, and Embase until May 2017. Only RCTs were included, and a meta-analysis was performed where appropriate. Subjects were women undergoing IVF treatment with or without a history of recurrent implantation failure and women with idiopathic RPL. The assessment focused on the efficacy of commonly used immunomodulators such as intravenous (IV) immunoglobulin, lymphocyte immunotherapy, intralipid, intrauterine infusion of granulocyte colony-stimulating factor (G-CSF) and peripheral blood mononuclear cells, subcutaneous administration of tumor necrosis factor (TNF)-alpha inhibitors, leukemia inhibitory factor, and oral administration of glucocorticoids. The primary outcomes were live birth rate and miscarriage rate; the secondary outcome was clinical pregnancy rate. Of the 7,226 publications identified, 53 were selected during the initial screening; 30 satisfied the selection criteria and were included in this review. The authors concluded that the available medical literature showed controversial results regarding the role of immunotherapy in improving reproductive outcomes. This study did not demonstrate a role for immunotherapy in improving the live birth rate in women undergoing IVF treatment or in the prevention of idiopathic RPL. Currently, immunotherapy should be used in the context of research and should not be employed in routine clinical practice to improve reproductive outcomes.
In another RCT, Al-Zebeidi et al. (2020) examined the effect of empiric intralipid infusion therapy on pregnancy outcomes for patients with unexplained recurrent implantation failure (RIF) undergoing ICSI. A total of 142 patients with a history of unexplained RIF (three or more cycles) were included in this study. Patients were randomized into two groups: the study group (n = 71) and the control group (n = 71). The study group received a 20% intralipid infusion on the day of embryo transfer (ET) and a second dose on the day of the pregnancy test. The clinical pregnancy rate in the study group was 36.6% (n = 26) compared to 28.2% (n = 20) in the control group (odds ratio [OR] 1.47, confidence interval [CI]: 0.72 to 2.98, p = 0.282). The live birth rate in the study group was 18.3% (n = 13) and 14.1% (n = 10) in the control group (OR 1.37, CI: 0.55 to 3.36, p = 0.49). No side effects of intralipid therapy were reported during the study period. There was an improvement in the pregnancy rate among women with unexplained RIF who received empiric intralipid infusion therapy; however, this improvement did not reach statistical significance.
Intrauterine Administration of Human Chorionic Gonadotropin (hCG) for Subfertile Women Undergoing Assisted Reproduction
Craciunas and colleagues (2018) examined whether intra-uterine (intra-cavity) administration of hCG (IC-hCG) around the time of embryo transfer (ET) improves clinical outcomes in sub-fertile women undergoing assisted reproduction. These investigators performed searches on January 9, 2018, using Cochrane methods. They looked for RCTs evaluating IC-hCG around the time of ET, irrespective of language and country of origin. Two review authors independently selected studies, assessed risk of bias, extracted data from studies, and attempted to contact study authors when data were missing. They performed statistical analysis using Review Manager 5. These researchers assessed evidence quality using GRADE methods. Primary outcomes were live birth and miscarriage; secondary outcomes were clinical pregnancy rate and complications. A total of 17 RCTs examined the effects of IC-hCG administration for 4,751 sub-fertile women undergoing assisted reproduction; IC-hCG was administered in variable doses at different times before the ET. hCG was obtained from the urine of pregnant women or from cell cultures using recombinant DNA technology. Most studies (12/17) were at high risk of bias in at least one of the seven domains assessed. Common problems included unclear reporting of study methods and lack of blinding. The main limitations for evidence quality were high risk of bias and serious imprecision. For analyses of live birth and clinical pregnancy, there was considerable heterogeneity (I² > 75%), and therefore, these researchers presented subgroups for dosage and stage of ET. Exploration for sources of heterogeneity revealed two key pre-specified variables as important determinants: stage of ET (cleavage versus blastocyst stage) and dose of IC-hCG (less than 500 international units (IU) versus greater than or equal to 500 IU). They performed meta-analyses within subgroups defined by stage of embryo and dose of IC-hCG. Live birth rates among women having cleavage-stage ET with an IC-hCG dose of less than 500 IU compared to women having cleavage-stage ET without IC-hCG showed no benefit of the intervention and would be consistent with no substantive difference or disadvantage of indeterminate magnitude (risk ratio (RR) 0.76, 95% CI: 0.58 to 1.01; 1 RCT; 280 participants; I² = 0%; very low-quality evidence). In a clinic with a live birth rate of 49% per cycle, use of IC-hCG of less than 500 IU would be associated with a live birth rate ranging from 28% to 50%. Results showed an increase in live birth rate in the subgroup of women undergoing cleavage-stage ET with an IC-hCG dose of greater than or equal to 500 IU compared to women having cleavage-stage ET without IC-hCG (RR 1.57, 95% CI: 1.32 to 1.87; 3 RCTs; 914 participants; I² = 0%; moderate-quality evidence). At a clinic with a live birth rate of 27% per cycle, use of IC-hCG of greater than or equal to 500 IU would be associated with a live birth rate ranging from 36% to 51%. Results showed no substantive differences in live birth among women having blastocyst-stage ET with an IC-hCG dose of greater than or equal to 500 IU compared to women having blastocyst-stage ET without IC-hCG (RR 0.92, 95% CI: 0.80 to 1.04; 2 RCTs; 1,666 participants; I² = 0%; moderate-quality evidence). At a clinic with a live birth rate of 36% per cycle, use of IC-hCG of greater than or equal to 500 IU would be associated with a live birth rate ranging from 29% to 38%. Evidence for clinical pregnancy among women having cleavage-stage ET with an IC-hCG dose of less than 500 IU showed no benefit of the intervention and would be consistent with no substantive difference or disadvantage of indeterminate magnitude (RR 0.88, 95% CI: 0.70 to 1.10; 1 RCT; 280 participants; I² = 0%; very low-quality evidence). Results showed an increase in clinical pregnancy rate in the subgroup of women having cleavage-stage ET with an IC-hCG dose of greater than or equal to 500 IU compared to women having cleavage-stage ET without IC-hCG (RR 1.49, 95% CI: 1.32 to 1.68; 12 RCTs; 2,186 participants; I² = 18%; moderate-quality evidence). Results showed no substantive differences in clinical pregnancy among women having blastocyst-stage ET with an IC-hCG dose of greater than or equal to 500 IU (RR 0.99, 95% CI: 0.85 to 1.15; 4 RCTs; 2,091 participants; I² = 42%; moderate-quality evidence) compared to women having blastocyst-stage ET with no IC-hCG. No RCTs examined blastocyst-stage ET with an IC-hCG dose of less than 500 IU. These researchers were uncertain whether miscarriage was influenced by intra-uterine hCG administration (RR 1.04, 95% CI: 0.81 to 1.35; 11 RCTs; 3,927 participants; I² = 0%; very low-quality evidence). Reported complications included ectopic pregnancy (4 RCTs; 1,073 participants; 4 events overall), heterotopic pregnancy (1 RCT; 495 participants; 1 event), intra-uterine death (3 RCTs; 1,078 participants; 22 events), and triplets (1 RCT; 48 participants; 3 events). Events were few, and very low-quality evidence was insufficient to permit conclusions to be drawn. The authors concluded that there was moderate-quality evidence that women undergoing cleavage-stage transfer using an IC-hCG dose of greater than or equal to 500 IU had an improved live birth rate. There was insufficient evidence for IC-hCG treatment for blastocyst transfer. There should be further trials with live birth as the primary outcome to identify the groups of women who would benefit the most from this intervention. There was no evidence that miscarriage was reduced following IC-hCG administration, irrespective of embryo stage at transfer or dose of IC-hCG. Events were too few to allow conclusions to be drawn with regard to other complications.
Intrauterine Injection/Infusion of Platelet Rich Plasma (PRP) for the Treatment of Female Infertility
Maleki-Hajiagha and colleagues (2020) stated that previous studies have provided conflicting results regarding the use of platelet-rich plasma (PRP) in women undergoing IVF or ICSI. In a systematic review and meta-analysis, these researchers examined the effect of the intrauterine infusion of PRP on the outcome of ET in women undergoing IVF/ICSI. They searched databases, including PubMed, Embase, Scopus, Web of Science, and the Cochrane Database of Clinical Trials (CENTRAL). Meta-analysis using a random-effects model was carried out to calculate the pooled estimates. A total of 7 studies involving 625 patients (311 cases and 314 controls) were included. The probability of chemical pregnancy (n = 3, RR: 1.79, 95% CI: 1.29 to 2.50; p < 0.001, I² = 0%), clinical pregnancy (n = 7, RR: 1.79, 95% CI: 1.37 to 2.32; p < 0.001, I² = 16%), and implantation rate (n = 3, RR: 1.97, 95% CI: 1.40 to 2.79; p < 0.001, I² = 0%) was significantly higher in women who received PRP compared with the control group. There was no difference between women who received PRP compared with the control group regarding miscarriage (RR: 0.72, 95% CI: 0.27 to 1.93; p = 0.51, I² = 0%). Following the intervention, endometrial thickness increased in women who received PRP compared to the control group (SMD: 1.79, 95% CI: 1.13 to 2.44; p < 0.001, I² = 64%). The authors concluded that the findings of this systematic review suggested that PRP is an alternative treatment strategy in patients with thin endometrium and recurrent implantation failure (RIF). Moreover, these researchers stated that further prospective, large, and high-quality RCTs are needed to identify the subpopulation that would most benefit from PRP.
The Practice Committee of the American Society for Reproductive Medicine’s guideline on “Evidence-based treatments for couples with unexplained infertility” (2020) did not mention PRP as a management option.
Lin and associates (2021) noted that clinical studies for the effectiveness of PRP in improving uterine endometrial function remain controversial. Most studies suggested that PRP treatment resulted in positive reproductive results in patients with thin endometrium, RIF, chronic endometritis (CE), and Asherman syndrome (AS); however, the best dosage and timing of PRP application remain unknown. Few studies examined the underlying mechanisms of the PRP treatment. PRP might improve endometrial receptivity via the improvement of cell proliferation, vascularization, anti-inflammatory properties, and the reduction in the degree of fibrosis, with the help of the concentrated peptides, growth factors, and cytokines in PRP. Moreover, these researchers stated that for its potential clinical application, further explication of the mechanism is needed. They noted that although increasing evidence suggests the possible value of PRP treatment on the endometrium of infertile women, more carefully designed studies, especially RCTs, on larger scales are needed. Furthermore, the standard PRP preparation procedure and the strict indication of the PRP treatment should be published; studies and follow-ups are needed on the long-term health and complications of the resulting child(ren).
Mouanness and co-workers (2021) stated that endometrial receptivity and thickness play an important role in achieving a pregnancy. Intrauterine autologous PRP infusion has been used in infertile women with RIF and thin endometrial lining thickness (EMT). These investigators carried out a literature search in PubMed for studies including in-vitro, animal, and human studies, as well as in abstracts presented at national conferences. Animal studies demonstrated a decrease in the expression of inflammatory markers and fibrosis, and increased endometrial proliferation rate, increased expression of proliferative genes, and increased pregnancy rates. The in-vitro studies showed that PRP was associated with increased stromal and mesenchymal cell proliferation, increased expression of regenerative enzymes, and enhancement in cell migration. In infertile women undergoing ART, one randomized clinical trial showed that PRP intrauterine infusion improved EMT, implantation rate, and clinical pregnancy rate (CPR) in patients with thin EMT, while three other trials involving subjects with RIF showed conflicting results related to CPR. Case series and cohort studies showed conflicting results pertaining to CPR. The authors concluded that data to date suggested that PRP may be beneficial in improving endometrial thickness and endometrial receptivity; however, they stated that further large, prospective, and high-quality trials are needed to examine its effect and to identify the population of patients that would benefit the most.
Intrauterine Insemination (IUI)
Statistics show that the cumulative incidence of IUI pregnancies tends to level off after four IUI cycles for heterosexual couples, whereas the cumulative incidence of IUI pregnancies continues to increase significantly with more than four cycles for same-sex female couples and unpartnered females (Capinello et al., 2021; Johal et al., 2021; Linara-Demakakou et al., 2020; Morshedi et al., 2003; Quetrell et al., 2023; Soria et al., 2012).
In a randomized controlled trial (RCT; the FASTT Trial), Reindollar et al. (2010) examined the value of gonadotropin/intra-uterine insemination (FSH/IUI) therapy for infertile women aged 21 to 39 years. Participants were couples with unexplained infertility. Couples were randomized to receive either conventional treatment (n = 247) with 3 cycles of clomiphene citrate (CC)/IUI, 3 cycles of FSH/IUI, and up to 6 cycles of IVF, or an accelerated treatment (n = 256) that omitted the 3 cycles of FSH/IUI. Main outcome measures included the time it took to establish a pregnancy that led to a live birth and cost-effectiveness, defined as the ratio of the sum of all health insurance charges between randomization and delivery divided by the number of couples delivering at least 1 live-born baby. An increased rate of pregnancy was observed in the accelerated arm (hazard ratio [HR], 1.25; 95% confidence interval [CI]: 1.00 to 1.56) compared with the conventional arm. Median time to pregnancy was 8 and 11 months in the accelerated and conventional arms, respectively. Per cycle pregnancy rates for CC/IUI, FSH/IUI, and IVF were 7.6%, 9.8%, and 30.7%, respectively. Average charges per delivery were $9,800 lower (95% CI: $25,100 lower to $3,900 higher) in the accelerated arm compared to conventional treatment. The observed incremental difference was a savings of $2,624 per couple for accelerated treatment and 0.06 more deliveries. The authors concluded that a randomized clinical trial demonstrated that FSH/IUI treatment was of no added value.
The authors stated that beginning treatment with CC/IUI will result in pregnancy in nearly 25% of the couples, with minimal risk of multiple births and at a low cost. As clinical practice moves to limiting the number of embryos transferred during IVF procedures in young women to 1 or 2 embryos, eliminating gonadotropin/IUI from the stepwise infertility paradigm will result in pregnancies with the lowest possible risk for multiple births. Compared with conventional infertility treatment, and when the woman is younger than 40 years, an accelerated approach to IVF that starts with CC/IUI but eliminates gonadotropin/IUI results in a shorter time to pregnancy, with fewer treatment cycles, and at a suggested cost savings.
In a secondary analysis of 2 RCTs (the FASTT Trial and the FORT-T Trial), Kaser et al. (2014) examined if Day-3 FSH and E2 levels at the upper limits of normal affect live-birth rates and treatment trajectory in a conventional versus "fast track" treatment program for IVF. Infertile women aged 21 to 42 years were randomized to conventional or accelerated treatment with controlled ovarian hyperstimulation (COH)-IUI and/or IVF (n = 603 patients contributing 2,717 total cycles). Patients were stratified according to basal FSH and E2: FSH less than 10 mIU/ml and E2 less than 40 pg/ml (group 1A), FSH less than 10 mIU/ml and E2 40 pg/ml or higher (group 1B), FSH 10 to 15 mIU/ml and E2 less than 40 pg/ml (group 2A), and FSH 10 to 15 mIU/ml and E2 40 pg/ml or higher (group 2B). Main outcome measures included the number of cancelled cycles, dis-enrollment for poor response, and cumulative live-birth rates per couple. Women in groups 2A and 2B were more likely to have cancelled cycles and be dis-enrolled for poor response. While no live births occurred in group 2B during COH-IUI (0/19 couples, 0/58 cycles), IVF still afforded these patients a reasonable chance of success (6/18 couples, 6/40 cycles, 33.3% live-birth rate per couple). The specificity and positive predictive value (PPV) of basal FSH of 10 to 15 mIU/ml and E2 40 pg/ml or higher for no live birth during COH-IUI treatment were both 100%. The authors concluded that women who initiated infertility treatment with FSH of 10 to 15 mIU/ml and E2 40 pg/ml or higher on Day-3 testing were unlikely to achieve live birth after COH-IUI treatment.
Bordewijk et al. (2019) stated that in women with normo-gonadotropic anovulation who ovulate but do not conceive after 6 cycles with clomiphene citrate (CC), medication is usually switched to gonadotrophins, with or without IUI. The cost-effectiveness of these changes in policy is unknown. These researchers examined if 6 cycles of ovulation induction with gonadotrophins are more cost-effective than 6 cycles of ovulation induction with CC with or without IUI in normo-gonadotropic anovulatory women not pregnant after 6 ovulatory cycles with CC. They carried out an economic evaluation of ovulation induction with gonadotrophins compared with CC with or without IUI in a 2-by-2 factorial multi-center RCT in normo-gonadotropic anovulatory women not pregnant after 6 ovulatory cycles with CC. Between December 2008 and December 2015, women were allocated to 6 cycles with gonadotrophins plus IUI, 6 cycles with gonadotrophins plus intercourse, 6 cycles with CC plus IUI, or 6 cycles with CC plus intercourse. The primary outcome was conception leading to a live birth achieved within 8 months of randomization. These investigators carried out a cost-effectiveness analysis on direct medical costs. They calculated the direct medical costs of ovulation induction with gonadotrophins versus CC and of IUI versus intercourse in 6 subsequent cycles. They included costs of medication, cycle monitoring, interventions, and pregnancy leading to live birth. Resource use was collected from the case report forms, and unit costs were derived from various sources. These researchers calculated incremental cost-effectiveness ratios (ICER) for gonadotrophins compared to CC and for IUI compared to intercourse. They used non-parametric bootstrap re-sampling to examine the effect of uncertainty in their estimates. The analysis was carried out according to the intention-to-treat (ITT) principle. The authors allocated 666 women in total to gonadotrophins and IUI (n = 166), gonadotrophins and intercourse (n = 165), CC and IUI (n = 163), or CC and intercourse (n = 172). Mean direct medical costs per woman receiving gonadotrophins or CC were €4,495 versus €3,006 (cost difference of €1,475 (95% CI: €1,457 to €1,493)). Live-birth rates were 52% in women allocated to gonadotrophins and 41% in those allocated to CC (relative risk (RR) 1.24; 95% CI: 1.05 to 1.46). The ICER was €15,258 (95% CI: €8,721 to €63,654) per additional live birth with gonadotrophins. Mean direct medical costs per woman allocated to IUI or intercourse were €4,497 versus €3,005 (cost difference of €1,510 (95% CI: €1,492 to €1,529)). Live-birth rates were 49% in women allocated to IUI and 43% in those allocated to intercourse (RR = 1.14; 95% CI: 0.97 to 1.35). The ICER was €24,361 (95% CI: €-11,290 to €85,172) per additional live birth with IUI.
The authors concluded that gonadotrophins were more effective but more expensive than CC; thus, the use of gonadotrophins in women with normo-gonadotropic anovulation who have not conceived after 6 ovulatory CC cycles depends on society's willingness to pay for an additional child. In view of the uncertainty around the cost-effectiveness estimate of IUI, these data were insufficient to make recommendations on the use of IUI in these women. In countries where ovulation induction regimens are reimbursed, policymakers and healthcare professionals may use these findings in their guidelines.
Physiological, Hyaluronan-selected Intracytoplasmic Sperm Injection (PICSI)
Physiological, hyaluronan-selected intracytoplasmic sperm injection (PICSI) is a variation of intracytoplasmic sperm injection (ICSI) that uses hyaluronic acid (HA) to select sperm. The selection of sperm for ICSI by the hyaluronic acid binding method is based on the ability of competent mature sperm to attach themselves to HA through specific receptors found on the sperm plasma membrane. Sperm with diminished maturity, increased levels of chromosomal aberrations, or failed spermatogenetic membrane remodeling will not bind to HA. The selection of sperm bound to HA for ICSI may facilitate the selection of individual mature sperm with low levels of chromosomal aneuploidies and thus be associated with lower rates of miscarriage after ICSI (Rosen, 2024).
In a systematic review and meta-analysis, Lepine et al. (2019) evaluated the effectiveness and safety of advanced sperm selection techniques on assisted reproductive technologies (ART) outcomes. The analysis included eight randomized controlled trials (RCTs) (4,147 women) comparing advanced sperm selection techniques versus standard IVF, ICSI, or another technique. The authors reported that the quality of evidence ranged from very low to low. Primary outcomes measured were live birth and miscarriage per woman randomly assigned. Secondary outcome measures included clinical pregnancy per woman randomly assigned. Secondary adverse events measured included miscarriage per clinical pregnancy and fetal abnormality. The authors found that miscarriage risk was lower for patients undergoing ICSI with hyaluronic acid-selected sperm (PICSI) versus ICSI alone (3 to 6 percent for PICSI versus 7 percent with ICSI alone, risk ratio [RR] 0.61, 95% CI 0.45-0.83, 3,005 women); however, live birth rates were similar between the groups (RR 1.09, 95% CI 0.97-1.23, 2,903 women). The authors concluded that the evidence suggests that sperm selected by hyaluronic acid binding may have little or no effect on live birth or clinical pregnancy but may reduce miscarriage. The authors reported being uncertain of the effect of Zeta sperm selection on live birth, clinical pregnancy, and miscarriage due principally to the very low quality of the evidence for this intervention. They are also uncertain of the effect of the other selection techniques on live birth, miscarriage, or pregnancy. Further high-quality studies are required to evaluate whether any of these advanced sperm selection techniques can be recommended for use in routine practice.
Miller and colleagues (2019) noted that sperm selection strategies aimed at improving success rates of ICSI include binding to hyaluronic acid (herein termed hyaluronan). Hyaluronan-selected sperm have reduced levels of DNA damage and aneuploidy. Use of hyaluronan-based sperm selection for ICSI (so-called physiological ICSI [PICSI]) has been reported to reduce the proportion of pregnancies that end in miscarriage. However, the effect of PICSI on live birth rates is uncertain. In a parallel, 2-group, randomized trial (HABSelect), these investigators examined the efficacy of PICSI versus standard ICSI for improving live birth rates among couples undergoing fertility treatment. This study included couples undergoing an ICSI procedure with fresh embryo transfer at 16 assisted conception units in the United Kingdom. Eligible women (aged 18 to 43 years) had a BMI of 19 to 35 kg/m² and an FSH concentration of 3.0 to 20.0 mIU/ml or, if no FSH measurement was available, an AMH concentration of at least 1.5 pmol/L. Eligible men (aged 18 to 55 years) had not had a vasovasostomy or been treated for cancer in the 24 months before recruitment and were able, after at least 3 days of sexual abstinence, to produce freshly ejaculated sperm for the treatment cycle. Couples were randomly assigned (1:1) with an online system to receive either PICSI or a standard ICSI procedure. The primary outcome was full-term (greater than or equal to 37 weeks' gestational age [GA]) live birth, which was assessed in all eligible couples who completed follow-up. Between February 1, 2014, and August 31, 2016, a total of 2,772 couples were randomly assigned to receive PICSI (n = 1,387) or ICSI (n = 1,385), of whom 2,752 (1,381 in the PICSI group and 1,371 in the ICSI group) were included in the primary analysis. The term live birth rate did not differ significantly between PICSI (27.4% [379/1,381]) and ICSI (25.2% [346/1,371]) groups (OR 1.12, 95% CI: 0.95 to 1.34; p = 0.18). There were 56 serious adverse events (AEs) in total, including 31 in the PICSI group and 25 in the ICSI group; most were congenital abnormalities, and none was attributed to treatment. The authors concluded that compared with ICSI, PICSI did not significantly improve term live birth rates. Thus, these researchers stated that the wider use of PICSI is not recommended at present.
Martin and Woodland (2021) state that several studies reported improved fertility treatment outcomes when using PICSI compared with conventional ICSI; however, the majority of studies are underpowered. Recently, a large, multicenter, randomized controlled trial, known as the Hyaluronic Acid Binding Sperm Selection (HABSelect) trial, found a significant reduction in miscarriage rates with PICSI, but no significant effect on live birth rate. There are still many avenues through which PICSI may provide an advantage, subject to confirmation by future research, such as improved long-term health of offspring. Other advanced sperm selection techniques include intracytoplasmic morphologically selected sperm injection, magnetic-activated cell sorting, and Zeta potential sperm selection; however, the most recent Cochrane review concluded that there is currently insufficient evidence to ascertain whether these techniques improve clinical outcomes, such as live birth rates.
Sickle Cell Disease and Infertility Risks
Sickle cell disease (SCD) is a chronic, inherited blood disorder characterized by the production of abnormal hemoglobin S, which causes red blood cells to become rigid and sickle-shaped. This condition can result info a vaso-occlusive pain crises, anemia, and end-organ injury.
In a narrative review, Pecker and Cameron (2024) state that SCD and its treatments present infertility risks. The purpose of their review is to support clinicians in providing counselling about fertility and infertility risks to girls and women with SCD and their families. The authors state ovaries are considered an SCD end-organ and that there is growing evidence to support the claim that in SCD, the reproductive lifespan is reduced. They report that this is best substantiated for those with hemoglobin SS or hemoglobin Sβ0-thalassemia. The authors state that a treatment paradigm that acknowledges the risks of untreated SCD, the benefits of treating SCD, and the potential for compromised fertility in the future is warranted. Moreover, robust data addressing significant questions about menstruation, contraception, pregnancy, infertility, menopause and how these issues are affected by genotype and SCD therapies would allow clinicians to claim more solid ground and clarify recommendations. An updated treatment paradigm that coordinates optimizing SCD treatment with fertility care is indicated.
SCD-related fertility issues impact men and women alike. "The standard protocol for managing infertility remains identifying the source of the infertility—meaning whether the issue lies with the male or female in a relationship, or both. Just because the risk of infertility is higher in SCD does not preclude infertility from being caused by other factors" (Lai, 2022).
Stem Cell Therapy for the Treatment of Female Infertility
In a systematic review, Ahmadian and colleagues (2020) examined the evidence on stem cell therapy for ovarian disorders. These researchers evaluated different published studies on stem cell-based therapy for the treatment of various types of ovarian insufficiency and disorders such as premature ovarian insufficiency (POI) in the affected female population in animal or human clinical studies. They monitored 5 databases, including PubMed, Cochrane, Embase, Scopus, and ProQuest. A comprehensive online search was carried out using including criteria targeting application of stem cells in animal models for menopause. Two independent reviewers carefully evaluated titles and abstracts of studies. The stem cell type, source, dosage, route of administration were high-lighted in various POI animals models. Non-relevant and review articles were excluded. A total of 648 published studies were identified during the initial comprehensive search process from which 41 were selected according to designed criteria. Based on this analysis, stem cells could accelerate ovarian tissues rejuvenation, regulate systemic sex-related hormones levels and eventually increase fertility rate. The authors concluded that the evidence suggested that stem cell-based therapies could be considered as an alternative modality to deal with women undergoing POI.
Uterine Transplant (Donor Hysterectomy) for the Treatment of Infertility
Daolio and colleagues (2020) noted that uterine transplantation (UTx) associated with IVF restores fertility in women affected by absolute uterine factor infertility (AUFI). Pregnancies achieved both in women undergoing any solid organ transplantation and following IVF are associated with an increased risk of maternal and neonatal complications. In a systematic review, these investigators examined this risk in UTx-IVF treated women, focusing on the safety and efficacy features of the treatment. A total of 22 studies and 3 press releases reporting on 52 UTx-IVF treatments were identified. Regarding the safety of treatment, 38/52 (73.1%) of surgical procedures led to the restoration of uterine function in recipients, 12/52 (23.1%) of recipients experienced post-operative complications requiring hysterectomy, and 2/52 (3.8%) of procedures failed before uterine recipients' surgery due to intra-operative complications. Regarding the efficacy of treatment, results focused on transplanted patients showing full recovery of organ functioning: 16/38 (42.1%) of patients achieved a pregnancy, including 2 women who gave birth twice. UTx-IVF pregnancies led to 16 deliveries, and all newborns were healthy; 6 out of 16 (37.5%) UTx pregnancies faced major complications during gestation. Pre-term births (PTBs) occurred in 10/16 (62.5%) UTx deliveries. The authors concluded that these findings showed that the risk of gestational and delivery complications deserves important consideration in AUFI women receiving UTx-IVF treatments; however, these observations were preliminary and need to be revised after larger series of data are published. Moreover, these researchers stated that although the accuracy of UTx-IVF safety and efficacy outcomes could not be evaluated definitively until UTx centers provide additional, meaningful data from larger series of UTx cases treated homogeneously, they critically evaluated the following aspects. UTx surgery in recipients is mainly complicated by vascular impairments and uterine infections, which have a negative impact on graft survival and maintenance. The incidence of post-operative complications leading to hysterectomy in UTx recipients was estimated to be 23%, but this value could be underestimated.
The authors stated that this review had several drawbacks. Published studies represented only a small percentage of the cases actually performed by the time of writing, and this could have influenced the accuracy of the estimations of safety and efficacy in both UTx recipients and children, which could be potentially underestimated. As a matter of fact, more than 60 UTx procedures have been performed worldwide, and 18 babies have been delivered, but 50% of these cases have not yet been scientifically published. The majority of studies did not describe post-operative, maternal, and neonatal outcomes simultaneously, probably due to the different timings of occurrence concerning UTx surgery, gestational period, and delivery. Data were often published at a distance and reported in more than one study or referred to as personal communications. Furthermore, many studies did not capture the learning curve of the surgical teams at different centers worldwide, and it is hoped that future research will provide more standardized UTx surgical procedures.
Ricci and co-workers (2021) stated that UTx is an evolving procedure to allow for childbearing in women with AUFI. These researchers examined the available evidence using a comprehensive PubMed literature search. They carried out a systematic medical sub-headings search strategy with the terms "uterus transplant" and "uterine transplantation." Of the 75 full-text articles reviewed for eligibility, 68 were included in the qualitative synthesis. Of these, 9 were included in the meta-analysis on living donor uterine transplant, 5 on deceased donor uterine transplant, and 6 case reports of single uterine transplants. The authors concluded that UTx is a nascent field undergoing a rapid rate of evolution as programs mature their data and increase the number of procedures performed.
Malasevskaia and Al-Awadhi (2021) noted that UTx restores fertility in women with AUFI and allows the opportunity to conceive, experience gestation, and acquire motherhood. The number of cases being carried out is increasing dramatically, with detailed outcomes from 65 cases now available. Pregnancies achieved through UTx and following IVF were associated with an increased risk for further maternal and newborn complications. This review focused on the safety and efficacy of UTx, which is associated with significant risk, with approximately 25% of grafts removed because of complications. The authors concluded that UTx is realizable in women with uterine factor infertility; however, it is associated with a significant complication risk. The risk of the procedure and gestational and delivery complications deserve important consideration before receiving such treatments. Nevertheless, these observations are preliminary and should be revised after a larger series of data are published. Moreover, these investigators stated that further studies should concentrate on the safest operation method to minimize complications for the donor and recipient. Furthermore, further research is needed on the immunosuppressive protocol used before and during the pregnancy period. Long-term observation of the patients (recipients) after hysterectomy is demanded. As they undergo a significant intervention that changes the anatomy of pelvic floor muscles, the direction of ureters, and the placement of the ovaries, these may predispose to pelvic organ prolapse and urinary tract infections (UTIs) with further kidney damage. Additionally, these procedures could affect the vascular supply of pelvic organs and lower limbs.
Fronek and colleagues (2021) reported the results of the first 10 UTx procedures carried out at their institution. The program started in April 2016 as a 2-arm study comparing the efficacy of UTx from live donors (LD) and deceased donors (DD). Between April 2016 and April 2018, these researchers carried out 5 DD UTx and 5 LD UTx; 2 grafts had to be removed early due to thrombosis, and 1 graft was removed due to chronic rejection and previous herpes simplex infection at month 7. Graft survival was 70% at 1 year. Recipient survival was 100% at 2 years; LD survival was 100% at 3 years; and 3 live births have been achieved, 2 from an LD and 1 from a graft from a nulliparous DD. Vaginal anastomotic stenosis occurred in 63% (5/8) of grafts. Self-expanding stents have shown preliminary suitability for the treatment of vaginal stenosis; 3 recipients developed severe acute rejection. The authors concluded that the interim results of this study demonstrated mid-term viability in 70% of grafts. The LD UTx produced 2 live births, and the DD UTx produced 1 live birth. Moreover, these researchers stated that nulliparous donors should be considered for donation; however, their potential needs further clarification. These investigators also observed 4 miscarriages in 2 recipients. This preliminary report provided further evidence of the feasibility of UTx from both LDs and DDs.
Jones and associates (2021) stated that following the diagnosis of AUFI, women may experience considerable psychological harm as a result of a loss of reproductive function and the realization of permanent and irreversible infertility. Adoption enables women with AUFI and their partners to experience social and legal parenthood, also often providing benefits for the adopted child. Surrogacy offers the opportunity to have genetically related offspring. Outcomes are generally positive for both surrogates and the children born as a result. Uterine transplantation is the only option to restore reproductive anatomy and functionality. These researchers noted that more than 70 UTx cases have now been undertaken, and following at least 18 live births after successful procedures, UTx is now considered a feasible fertility-restoring treatment for women with AUFI. However, it is associated with considerable surgical and immunosuppressive-related risk and, based on cases performed so far, a greater than 25% risk of unplanned hysterectomy.
Brannstrom and colleagues (2021) noted that women with AUFI, because of uterine absence or the presence of a non-functional uterus, were regarded as being untreatable until 2014 when the first birth following UTx took place in Sweden. This proof-of-concept occurred in a woman with MRKH syndrome with congenital uterine absence, who received a uterus from a 61-year-old LD. Since then, several births after UTx have occurred in Sweden and subsequently in other countries, including both LD and DD transplants. The majority of the recipients were women with MRKH syndrome. The safety and effectiveness of UTx can be determined only when a complete study cohort of transplanted women has reached the definitive endpoint of graft hysterectomy. The different outcomes of transplanted women included graft failure, as well as graft survival with failure to achieve live birth or live births. Published data from a completed trial are not yet available. The results that these researchers had to rely on were reports of completed surgeries and interim outcomes that may be as early as a few months after surgery and up to several years after UTx. These investigators provided an update on all published clinical UTx data and major results, including live births up to mid-2021. The interim results of a number of UTx studies have been published. LD UTx procedures have been reported from 4 European countries (Sweden, the Czech Republic, Germany, and Spain), 4 Asian nations (Saudi Arabia, India, China, and Lebanon), as well as some from the U.S. DD UTx procedures have been reported from Turkey, the Czech Republic, the U.S., and Brazil. To the authors’ knowledge, there also exist unpublished UTx cases from some of the countries mentioned above and from at least 4 other countries (Serbia, France, Mexico, and Italy). They estimated that at least 80 UTx procedures have been carried out, resulting in more than 40 births. This study included only data from published, peer-reviewed research papers. The results of 62 UTx cases showed an overall surgical success rate, as defined by a technically successful transplantation with a subsequent regular menstrual pattern, of 76%. The success rates for LD and DD UTx procedures were 78% and 64%, respectively. The rate of serious post-surgical complications requiring invasive or radiological intervention was 18% for LDs and 19% for recipients. The cumulative live-birth rate in successful UTx procedures was estimated to be above 80%; 24 births after UTx have been reported, and the results showed a high rate of PTB, with an associated high proportion of respiratory distress syndrome. The authors concluded that UTx has proven to be a successful treatment for AUFI at several centers around the world. The modest success rate and the fairly high complication rate among LDs indicated that further research and development under strict governance are needed before this option should be widely offered.
Vaginal Sildenafil for the Treatment of Female Infertility
Check et al. (2004) examined whether sildenafil improves endometrial thickness better than vaginal estradiol (E2) in women with a history of thin endometria. Women who failed to attain an 8 mm endometrial thickness on either the oocyte retrieval cycle or their first frozen embryo transfer (ET) despite an oral graduated E2 regimen were treated again with graduated oral E2 and were randomly assigned to vaginal sildenafil or vaginal E2 therapy. Endometrial thickness was compared between the groups. The study found that neither vaginal E2 nor sildenafil significantly improved endometrial thickness or blood flow in the subsequent frozen ET cycle. The authors concluded that these data failed to corroborate previous claims that 25 mg sildenafil administered four times daily intra-vaginally can improve endometrial thickness.
Zinger et al. (2006) stated that vaginal sildenafil citrate has been shown to be useful in increasing endometrial thickness and achieving pregnancy in women with various uterine disorders. However, it failed to demonstrate favorable results in the setting of Asherman's syndrome, a condition characterized by the presence of uterine synechiae. These investigators successfully applied this treatment in two women noted to have inadequate endometrium after surgical resection of uterine synechiae. Both patients had a history of postpartum uterine curettage with subsequent secondary infertility. Asherman's syndrome was surgically demonstrated and treated in both patients. Post-operatively, both patients were noted to have a thin endometrium and failed to conceive despite fertility treatment. Subsequently, these women achieved pregnancy in the first treatment cycle with vaginal sildenafil citrate. Using trans-vaginal ultrasound, endometrial thickness was noted to improve when sildenafil citrate was administered. It is suspected that this medication causes selective vasodilatation, resulting in improved endometrial development.
Malinova et al. (2013) noted that the evaluation of endometrial receptivity remains a challenge in clinical practice. Ultrasound evaluation of endometrial thickness and texture, as well as measurement of uterine artery blood flow, has been used for endometrial assessment. These researchers investigated the role of a combination of sildenafil citrate and serophene on endometrial thickness, endometrial volume, endometrial flow index (FI), and vascular flow index (VFI) on angiohistogram, as well as resistance index (RI) and pulsatility index (PI) to the uterine artery on the day of hCG, in predicting IUI outcomes in infertile women. A total of 42 patients with anovulatory infertility were randomly selected. In the sildenafil citrate plus serophene group (Group I), patients received 25 mg sildenafil citrate (Silden) vaginally and serophene 100 to 150 mg orally, while the serophene group (Group II) received 100 to 150 mg of serophene orally. The mean endometrial thickness and endometrial volume were 11.8 ± 2.6 vs. 10.2 ± 2.8 and 5.2 ± 1.4 vs. 3.6 ± 1.8, respectively, in Group I and Group II (p < 0.05). There was a significant decrease in PI and RI to the uterine artery in Group I. The authors concluded that the combination of sildenafil citrate and serophene is an effective agent as a first-line treatment for ovulation induction. However, this was a relatively small study, and its findings were confounded by the combined use of sildenafil and serophene.
Soliman and colleagues (2017) developed and characterized in-situ thermos-sensitive gels for the vaginal administration of sildenafil as a potential treatment for endometrial thinning occurring as a result of using clomiphene citrate for ovulation induction in women with type II eugonadotrophic anovulation. While sildenafil has shown promising results in the treatment of infertility in women, the lack of vaginal pharmaceutical preparation and the side effects associated with oral sildenafil limit its clinical effectiveness. Sildenafil citrate in-situ forming gels were prepared using different grades of Pluronic (PF-68 and PF-127). Muco-adhesive polymers such as sodium alginate and hydroxyethyl cellulose were added to the gels in different concentrations, and the effect on gel properties was studied. The formulations were evaluated in terms of viscosity, gelation temperature (Tsol-gel), muco-adhesion properties, and in-vitro drug release characteristics. Selected formulations were evaluated in women with clomiphene citrate failure due to thin endometrium (Clinicaltrial.gov identifier NCT02766725). The Tsol-gel decreased with increasing PF-127 concentration and was modulated by the addition of PF-68 to be within the acceptable range of 28 to 37 °C. Increasing Pluronic concentration increased gel viscosity and muco-adhesive force but decreased the drug release rate. Clinical results showed that the in-situ sildenafil vaginal gel significantly increased endometrial thickness and uterine blood flow with no reported side effects. Furthermore, these results were achieved with a lower frequency and duration of drug administration. The authors concluded that sildenafil thermos-sensitive vaginal gels might improve the potential for pregnancy in anovulatory patients with clomiphene citrate failure due to thin endometrium. These preliminary findings need to be validated by well-designed studies.
Vasodilators for Women Undergoing Fertility Treatment
- evidence was insufficient to show that vasodilators increased the live-birth rate in women undergoing fertility treatment;
- low-quality evidence suggested that vasodilators may increase clinical pregnancy rates in comparison with placebo or no treatment, and
- evidence was insufficient to show whether any particular vasodilator, administered alone or in combination with other active medications, was superior, and evidence was insufficient to allow the review authors to reach any conclusions regarding adverse effects.
They stated that adequately powered studies are needed so that each treatment can be evaluated more accurately.
In a Cochrane review, Gutarra-Vilchez and colleagues (2018) examined the safety and effectiveness of vasodilators in women undergoing fertility treatment. These investigators searched the following electronic databases, trial registers, and websites: the Cochrane Gynaecology and Fertility Group (CGF) Specialized Register of controlled trials, the Cochrane Central Register of Controlled Trials via the Cochrane Register of Studies Online (CRSO), Medline, Embase, PsycINFO, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Knowledge, the Open System for Information on Grey Literature in Europe (OpenSIGLE), the Latin American and Caribbean Health Science Information Database (LILACS), clinical trial registries, and the reference lists of relevant articles. They conducted the search in October 2017 and applied no language restrictions. RCTs comparing vasodilators alone or in combination with other treatments versus placebo or no treatment, or versus other agents in women undergoing fertility treatment, were selected for analysis. Four review authors independently selected studies, assessed risk of bias, extracted data, and calculated RRs. They combined study data using a fixed-effect model and assessed evidence quality using GRADE methods. The primary outcomes were live birth or ongoing pregnancy and vasodilator side effects. Secondary outcomes included clinical pregnancy, endometrial thickness, multiple pregnancy, miscarriage, and ectopic pregnancy. These investigators included 15 studies with a total of 1,326 women. All included studies compared a vasodilator versus placebo or no treatment. They judged most of these studies as having unclear risk of bias. Overall, the quality of evidence was low to moderate for most outcomes. The main limitations were imprecision due to low numbers of events and participants, and risk of bias due to unclear methods of randomization. Vasodilators probably made little or no difference in rates of live birth compared with placebo or no treatment (RR 1.18, 95% CI 0.83 to 1.69; 3 RCTs; n = 350; I² = 0%; moderate-quality evidence) but probably increased overall rates of side effects, including headache and tachycardia (RR 2.35, 95% CI: 1.51 to 3.66; 4 RCTs; n = 418; I² = 0%; moderate-quality evidence). Evidence suggested that if 236 per 1,000 women achieved live birth with placebo or no treatment, then between 196 and 398 per 1,000 will do so with the use of vasodilators. Compared with placebo or no treatment, vasodilators may slightly improve clinical pregnancy rates (RR 1.45, 95% CI: 1.19 to 1.77; 11 RCTs; n = 1,054; I² = 6%; low-quality evidence). Vasodilators probably made little or no difference in rates of multiple gestation (RR 1.15, 95% CI: 0.55 to 2.42; 3 RCTs; n = 370; I² = 0%; low-quality evidence), miscarriage (RR 0.83, 95% CI 0.37 to 1.86; 3 RCTs; n = 350; I² = 0%; low-quality evidence), or ectopic pregnancy (RR 1.48, 95% CI: 0.25 to 8.69; 2 RCTs; n = 250; I² = 5%; low-quality evidence). All studies found benefit for endometrial thickening, but reported effects varied (I² = 92%) and ranged from a mean difference (MD) of 0.80 higher (95% CI: 0.18 to 1.42) to 3.57 higher (95% CI: 3.01 to 4.13) with very low-quality evidence, so these researchers were uncertain how to interpret these results. The authors concluded that evidence was insufficient to show whether vasodilators increase the live birth rate in women undergoing fertility treatment. However, low-quality evidence suggested that vasodilators may slightly increase clinical pregnancy rates. Moderate-quality evidence showed that vasodilators increased overall side effects in comparison with placebo or no treatment. These investigators stated that adequately powered studies are needed so that each treatment can be evaluated more accurately.
EMMA (Endometrial Microbiome Metagenomic Analysis) and ALICE (Analysis of Infectious Chronic Endometritis)
Endometrial Microbiome Metagenomic Analysis (EMMA) (Igenomix) is a test to evaluate the microbial composition of the endometrium in women undergoing assisted reproductive treatments or experiencing recurrent implantation failure or pregnancy loss. EMMA uses advanced molecular techniques to identify and quantify bacteria present in the endometrium, distinguishing between beneficial species such as Lactobacillus, which support a healthy uterine environment, and pathogenic bacteria that may contribute to chronic endometritis and infertility. By providing a detailed profile of the endometrial microbiome, EMMA is intended to assist clinicians to tailor treatments, such as targeted antibiotics or probiotics, to restore microbial balance and improve conditions for embryo implantation. The test is often performed alongside Analysis of Infectious Chronic Endometritis (ALICE), which specifically screens for chronic endometritis.
Iwami et al. (2025) investigated whether personalized interventions guided by EMMA and ALICE could improve pregnancy outcomes and reduce time to conception in women with recurrent implantation failure or recurrent pregnancy loss. Conducted across 14 IVF centers in Japan, the prospective cohort included 527 women under 42 years old. Endometrial biopsies were analyzed using next-generation sequencing to classify patients into normal, abnormal (dysbiosis), or mild dysbiosis/ultralow biomass groups. Treatment was tailored to microbiota profiles: no intervention for normal cases, antibiotics followed by probiotics for abnormal cases, and probiotics alone for mild or ultralow profiles. Results showed that while overall ongoing pregnancy rates were similar across groups, Kaplan–Meier analysis revealed that women with dysbiosis who received targeted therapy achieved pregnancy significantly earlier than untreated groups, particularly within six to twelve months. Subgroup analysis indicated that patients with dysbiosis but negative ALICE results responded best to treatment, and age emerged as the only significant predictor of cumulative pregnancy rates, with older women benefiting most from microbiota correction. The study reported no severe adverse events, only minor antibiotic-related rashes. Limitations included potential contamination during sampling, inability of sequencing to distinguish live from dead bacteria, exclusion of fungi and viruses, and uncertainty about the pathogenic role of some bacteria found in healthy women.
Post-Coital Testing
An ASRM Committee Opinion (2021) explicitly states that the postcoital test (Simms-Huhner test) "is no longer recommended for the evaluation of infertile women" due to poor reproducibility, subjectivity, and lack of impact on clinical management. A JAMA review similarly states that "the use of the postcoital test…is not recommended" (Carson & Kallen, 2021).
Assisted Hatching
A 2021 Cochrane review (39 RCTs, 7,249 women) found that assisted hatching showed no improvement in live birth rates (OR 1.09, 95% CI 0.92–1.29) and was associated with an increased risk of multiple pregnancy (OR 1.38, 95% CI 1.13–1.68) (Lacey, et al., 2021). An ASRM guideline (2022) on assisted hatching similarly notes that the evidence for benefit is limited and the procedure carries risks including embryo damage and increased monozygotic twinning.
Endometrial biopsy
An ASRM Committee Opinion (2021) does not recommend endometrial biopsy as part of the routine infertility evaluation. However, endometrial biopsy may be indicated in specific clinical scenarios (e.g., suspected chronic endometritis or endometrial pathology).
Hormonal Evaluation of Male Infertility
Endocrine evaluation with FSH and testosterone is indicated for men with oligospermia (10 million sperm/mL), and further evaluation with LH and prolactin is indicated only when testosterone is low (300 ng/dL). Guidelines from the American Urologic Association (AUA) and the ASRM do not recommend routine measurement of growth hormone, ACTH, estrogens, or 17-hydroxyprogesterone as part of the standard male infertility workup (Schlegel, et al., 2021; Brannigan, et al,, 2024). Growth hormone testing is not part of any major guideline's recommended male infertility workup; the limited research on GH in subfertile men consists of small studies with no established clinical utility (Fujisawa, et al., 2002). Similarly, routine ACTH and estrogen testing are not recommended in standard male infertility evaluation.
Testosterone therapy
Updated guidelines from the AUA and ASRM reaffirmed that exogenous testosterone therapy should not be prescribed for males interested in current or future fertility (Clinical Principle), as it suppresses spermatogenesis and can cause oligospermia or azoospermia (Brannigan, et al., 2024).
Glossary of Terms
| Term | Definition |
|---|---|
| Agglutination | clumping spermatozoa in the ejaculate |
| Amenorrhea | condition in which a woman does not have menstrual periods |
| Aneuploidy | abnormal number of chromosomes in a cell. The majority of embryos with aneuploidies are not compatible with life. |
| Anovulation | condition in which a woman does not ovulate or ovulates rarely |
| Anti-sperm antibody test | a test used to determine if antibodies on the surface of sperm are interfering with the ability of sperm to move, penetrate the cervical mucus, or fertilize and egg |
| Artificial insemination | general term for the procedure in which sperm are inserted directly into a woman's cervix, fallopian tubes, or uterus |
| Aspermia | lack of external ejaculation |
| Assisted hatching | ART procedure in which the zona pellucida of an embryo is either thinned or perforated by chemical, mechanical or laser methods |
| Assisted reproduction technology (ART) | interventions that include the in vitro handling of both human oocytes and sperm or of embryos for the purpose of reproduction. This includes, but is not limited to, IVF and embryo transfer (ET), intracytoplasmic sperm injection (ICSI), embryo biopsy, preimplantation genetic testing (PGT), assisted hatching, gamete intrafallopian transfer (GIFT), zygote intrafallopian transfer (ZIFT), gamete and embryo cryopreservation, semen, oocyte and embryo donation, and gestational carrier cycles |
| Azoospermia | absence of spermatozoa in the ejaculate |
| Blastocyst | stage of preimplantation embryo development that occurs around day 5–6 after insemination or ICSI |
| Cleavage stage embryos | the early stage of embryo development where the fertilized egg is rapidly dividing into smaller cells, but the overall size of the embryo remains relatively constant. This stage typically occurs on days 2-3 after fertilization |
| Cryopreservation | process of slow freezing or vitrification to preserve biological material (e.g., gametes, zygotes, cleavage-stage embryos, blastocysts or gonadal tissue) at extreme low temperature for future use |
| Cryptorchidism | testis not in scrotal position within the neonatal period and, up to but not limited to, 1 year post birth. If the testis has not descended into the scrotum, this condition can cause primary testicular failure and increased risk of testicular cancer development |
| Donor insemination | process of placing laboratory processed sperm or semen from a man into the reproductive tract of a woman who is not his intimate sexual partner, for the purpose of initiating a pregnancy |
| Embryo | biological organism resulting from the development of the zygote, until eight completed weeks after fertilization, equivalent to 10 weeks of gestational age |
| Embryo bank | repository of cryopreserved embryos stored for future use |
| Embryo transfer cycle | an ART cycle in which one or more fresh or frozen/thawed embryos at cleavage or blastocyst stage are transferred into the uterus or Fallopian tube |
| Follicle stimulating hormone (FSH) | hormone produced in the pituitary gland that causes cells in the ovaries to grow |
| Frozen-thawed embryo transfer (FET) cycle | an ART procedure in which cycle monitoring is carried out with the intention of transferring to a woman, frozen/thawed or vitrified/warmed embryo(s)/blastocyst(s). Note: A FET cycle is initiated when specific medication is provided or cycle monitoring is started in the female recipient with the intention to transfer an embryo |
| Gamete intrafallopian transfer (GIFT) | an assisted reproductive technique that involves removing sperm and eggs, mixing them together and placing them into the fallopian tubes |
| Gonadotropin releasing hormone (Gn-RH) | hormone produced in the hypothalamus that is involved in triggering ovulation |
| Gonadotropin releasing hormone agonists and antagonists (GnRH agonist) | synthetic hormones that perform the same function as natural Gn-RH |
| Human chorionic gonadotropin (hCG) | hormone that can be used to trigger ovulation |
| Hypogonadotropic hypogonadism | also known as secondary hypogonadism, is a condition where the hypothalamus or pituitary gland fails to produce enough hormones that signal to the testes or ovaries to produce sex hormones like testosterone or estrogen. |
| Hysterosalpinogram | X-ray which involves injecting dye through the cervix into the uterus to determine if the fallopian tubes are open and the uterine cavity is normal |
| Hysteroscopy | procedure in which a thin, telescope-like instrument is inserted through the cervix into the uterus, allowing the doctor to see and photograph the area, and correct problems if needed |
| Iatrogenic infertility | impairment of fertility caused by surgery, radiation, chemotherapy, or other medical treatment affecting reproductive organs or processes (Huang et al, 2025) |
| Infertility | generally defined as an inability to get pregnant after a year of unprotected sexual intercourse or due to an impairment of a person's capacity to reproduce either as an individual or with his/her partner |
| Intracytoplasmic sperm injection (ICSI) | laboratory procedure in which sperm and eggs are retrieved from both partners. A single spermatozoon (sperm) is injected directly into an oocyte cytoplasm (egg), then the fertilized egg is implanted into the woman's uterus |
| Intra-uterine insemination (IUI) | artificial insemination technique in which sperm are put directly into a woman's uterus at the time they are ovulating to attempt a pregnancy |
| In vitro fertilization (IVF) | assisted reproductive technique that involves removing sperm and eggs, fertilizing them in a laboratory, then placing a fertilized egg in the uterus |
| Luteinizing hormone | hormone that triggers ovulation |
| Luteal phase | second half of the menstrual cycle |
| Morphology | size and shape of sperm |
| Motility | ability of sperm to move by themselves |
| Oligospermia | when a man has too few sperm to fertilize an egg normally |
| Ovulation | when the ovaries release a mature egg that is ready for fertilization |
| Oocyte | a developing egg |
| Oocyte donation | use of oocytes from an egg donor for reproductive purposes |
| Ovum | a mature egg |
| Preimplantation genetic testing (PGT) | test performed to analyze the DNA from oocytes (polar bodies) or embryos (cleavage stage or blastocyst) for HLA-typing or for determining genetic abnormalities. These include: PGT for aneuploidies (PGT-A); PGT for monogenic/single gene defects (PGT-M); and PGT for chromosomal structural rearrangements (PGT-SR) |
| Zona pellucida | the glycoprotein coat surrounding the oocyte |
| Zygote | fertilized egg |
| Zygote intrafallopian transfer (ZIFT) | assisted reproductive technique similar to IVF that involves removing sperm and eggs, combining them outside the body, and inserting fertilized eggs into the fallopian tubes |
Source: Adapted from American Society for Reproductive Medicine (ASRM), 2017; WebMD, 2025
Appendix
Laboratory Services
The following numbers of laboratory services per cycle are considered medically necessary.
| Natural monitoring | Clomid monitoring | Clomid IUI | Inj Mon Cycle | Inj IUI | IVF | GIFT | FET Code | PM | |
|---|---|---|---|---|---|---|---|---|---|
| Transvaginal ultrasound | 2 | 6 | 6 | 8 | 10 | ||||
| Estradiol | 2 | 6 | 6 | 8 | 10 | 10 | 10 | 10 | |
| FSH | 2 | 6 | 6 | 8 | 10 | 10 | 10 | 10 | |
| LH | 2 | 6 | 6 | 8 | 10 | 10 | 10 | 10 | |
| Progesterone | 2Footnotes for progesterone* | 2Footnotes for progesterone* | 2Footnotes for progesterone* | 8 | 10 | 10 | 10 | 10 | 3 |
| hCG | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 3 |
Key: IUI: intra-uterine insemination; Inj: injection; Mon: monthly; IVF: in-vitro fertilization; GIFT: gamete intra-fallopian transfer; FET: frozen embryo transfer; PM: pregnancy monitoring; FSH: follicle stimulating hormone; LH: luteinizing hormone; hCG: human chorionic gonadotropin.
Footnotes for progesterone*Note: More than 2 progesterone measurements may be medically necessary for infertile women with irregular and prolonged menstrual cycles. For infertile women with regular menstrual cycles, a mid-luteal serum progesterone measurement (day 21 of a 28-day cycle) is considered medically necessary. For infertile women with irregular menstrual cycles, this test would need to be repeated at the mid-luteal phase and weekly thereafter until the next menstrual cycle starts.
| Medication | Standard Limit | FDA-recommended Dosing |
|---|---|---|
| Gonadotropins/Menotropins (Initial CycleFootnotes for Initial Cycle*) | ||
| Follitropin alfa (Gonal-f) 450 unit vial | 10 vials per 28 days | Dosing must be individualized for each person. Ovulation induction: First cycle starting dose is 75 IU daily with incremental adjustment of up to 37.5 IU after 14 days. If necessary, increase dose by same magnitude every 7 days (in general up to 35 days of treatment). The initial dose in subsequent cycles is individualized based on prior response. Maximum daily dose of 300 IU. ART: Starting dose of 150 IU per day until adequate follicular development (up to 10 days of therapy in most cases). In persons whose endogenous gonadotropin levels are suppressed, starting dose of 225 IU daily. Consider dose adjustment after 5 days based on response (adjust no more frequently than every 3-5 days by no more than 75-150 IU). Maximum daily dose of 450 IU.Source: Merck & Co., 2020 |
| Follitropin alfa (Gonal-f) 1050 unit vial | 6 vials per 28 days | |
| Follitropin alfa (Gonal-f RFF) 300/0.5ml pen injector | 15 cartridges per 28 days | Ovulation induction: first cycle starting dose of 75 IU daily for 14 days. If indicated by the ovarian response after the initial 14 days, adjust dose by up to 37.5 IU every 7 days. Continue until adequate ovarian response (up to 35 days). The initial dose in subsequent cycles is based on prior response. Maximum daily dose of 300 IU. ART: starting dose of 150 IU per day until adequate follicular development (up to 10 days of therapy in most cases). In patients whose endogenous gonadotropin levels are suppressed, starting dose of 150 IU per day (if under 35 years old) or 225 IU per day (if 35 years old or older). Adjust dose after 5 days based on response (adjust no more frequently than every 3-5 days by no more than 75-150 IU). Maximum daily dose of 450 IU. Source: Merck & Co., 2020 |
| Follitropin alfa (Gonal-f RFF) 450/0.75ml pen injector | 10 cartridges per 28 days | |
| Follitropin alfa (Gonal-f RFF) 900/1.5ml pen injector | 7 cartridges per 28 days | |
| Follitropin alfa (Gonal-f RFF) 75 unit vial | 60 vials per 28 days | |
| Follitropin beta (Follistim AQ) 150 unit cartridge | 30 cartridges per 28 days | Ovulation induction: starting dose of 50 IU daily for at least 7 days, increased by 25 to 50 IU at weekly intervals until adequate ovarian response. Maximum daily dose of 250 IU. Controlled ovarian stimulation as part of an in vitro fertilization or intracytoplasmic sperm injection cycle: starting dose of 200 IU daily for at least 7 days with subsequent doses adjusted up or down based upon ovarian response. Maximum daily dose of 500 IU. Source: Merck & Co., 2020 |
| Follitropin beta (Follistim AQ) 300 unit cartridge | 15 cartridges per 28 days | |
| Follitropin beta (Follistim AQ) 600 unit cartridge | 10 cartridges per 28 days | |
| Follitropin beta (Follistim AQ) 900 unit cartridge | 7 cartridges per 28 days | |
| Menotropins for injection (Menopur) 75 IU vials | For ART: Do not administer daily doses of Menopur or Menopur in combination with Bravelle that exceed 450 IU. Therapy should not exceed 20 days. |
Development of Multiple Follicles and Pregnancy in Ovulatory Women as Part of an ART Cycle: The recommended dosing scheme for persons undergoing IVF follows a stepwise approach and is individualized for each woman. The recommended initial dose of Menopur for women who have received a GnRH agonist for pituitary suppression is 225 IU. Menopur may be co-administered with Bravelle and the total initial dose when the products are combined should not exceed 225 IU (150 IU of Menopur and 75 IU of Bravelle or 75 IU of Menopur and 150 IU of Bravelle). Source: Ferring Pharmaceuticals, 2018 |
| hCG subcutaneous injections (Initial CycleFootnotes for Initial Cycle*) | ||
| Choriogonadotropin alfa (Ovidrel) prefilled syringe 250 mcg | 1 prefilled syringe | Undergoing Ovulation Induction (OI): 250 µg should be administered one day following the last dose of the follicle stimulating agent. Undergoing Assisted Reproductive Technologies (ART): 250 µg should be administered one day following the last dose of the follicle stimulating agent. |
| hCG intramuscular injections (Initial CycleFootnotes for Initial Cycle*) | ||
| Chorionic gonadotropin (Pregnyl) 5,000 U, 10,000 U | 1 vial | Induction of ovulation and pregnancy in the anovulatory, infertile woman in whom the cause of anovulation is secondary and not due to primary ovarian failure and who has been appropriately pretreated with human menotropins. (See prescribing information for menotropins for dosage and administration for that drug product.): 5,000 to 10,000 USP units 1 day following the last dose of menotropins. (A dosage of 10,000 USP units is recommended in the labeling for menotropins.) Source: Merck & Co., 2015 |
| Chorianic gonadotropin (Novarel) 5,000 U, 10,000 U | 1 vial | Induction of ovulation and pregnancy in the anovulatory, infertile woman in whom the cause of anovulation is secondary and not due to primary ovarian failure and who has been appropriately pretreated with human menotropins (See prescribing information for menotropins for dosage and administration for that drug product): 5,000 to 10,000 USP Units one day following the last dose of menotropins. (A dosage of 10,000 USP Units is recommended in the labeling for menotropins). Source: Ferring Pharmaceuticals, 2018 |
| GnRH Antagonists (Initial CycleFootnotes for Initial Cycle*) | ||
| Ganirelix acetate, 250 ug/0.5 ml (prefilled syringe) | Inhibition of premature LH surges in women undergoing controlled ovarian hyperstimulation: After initiating FSH therapy on Day 2 or 3 of the cycle, Ganirelix Acetate Injection 250 mcg may be administered subcutaneously once daily during the mid to late portion of the follicular phase. By taking advantage of endogenous pituitary FSH secretion, the requirement for exogenously administered FSH may be reduced. Treatment with Ganirelix Acetate should be continued daily until the day of hCG administration. Source: Merck & Co., 2020 |
|
| Cetrorelix acetate (Cetrotide), 0.25 mg |
|
Inhibition of premature LH surges in women undergoing controlled ovarian stimulation: Cetrotide 0.25 mg may be administered subcutaneously once daily during the early- to mid-follicular phase. Cetrotide 0.25 mg is administered on either stimulation day 5 (morning or evening) or day 6 (morning) and continued daily until the day of hCG administration. Source: EMD Serono, 2018 |
Key: ART: advanced reproductive technology; BMI: body mass index; FSH: follicle stimulating hormone; HCG: human chorionic gonadotropin; IU: international units; MDV: multiple dose vial; PCOS: polycystic ovarian syndrome; PFS: prefilled syringe; U: units.
Notes:
Footnotes for Initial Cycle* Refills based upon documentation in cycle sheets.
Some plans exclude infertility services for ovarian failure; please check benefit plan descriptions.
| Medication | Strength | FDA-recommended Dosing | Length of approval |
|---|---|---|---|
| FollitropinsFootnotes for Follitropins* | |||
| Follitropin alfa (Gonal-f) | 450 unit or 1050 unit vial | Male hypogonadotropic hypogonadism: after normal serum testosterone levels are reached, the recommended dose of Gonal-f is 150 IU administered subcutaneously three times per week. and the recommended dose of hCG is 1,000 USP units (or the dose required to maintain serum testosterone levels within the normal range) three times a week. The lowest dose of Gonal-f which induces spermatogenesis should be utilized. Maximum dose of Gonal-f is 300 IU three times per week. Gonal-f may need to be administered for up to 18 months to achieve adequate spermatogenesis. Source: EMD Serono, 2018 |
12 months for hypogonadotropic hypogonadism |
| Follitropin beta (Follistim AQ) | 150, 300, 600, 900 unit multi-dose cartridges | Induction of spermatogenesis in men with primary and secondary hypogonadotropic hypogonadism in whom the cause of infertility is not due to primary testicular failure: after normalization of serum testosterone levels, administer 450 IU per week (225 IU twice weekly or 150 IU three times weekly) of Follistim AQ Cartridge subcutaneously with the same pre-treatment hCG dose used to normalize testosterone levels. Source: Merck & Co., 2020 |
12 months for hypogonadotropic hypogonadism |
| hCG intramuscular injections | |||
| Examples: Pregnyl, Novarel, hCG | 10,000 unit 5,000 unit |
Varies: Prepubertal cryptorchidism not due to anatomical obstruction (Therapy is usually instituted in children between the ages of 4 and 9):
Selected cases of hypogonadotropic hypogonadism in males:
|
6 months for prepubertal cryptorchidism; 12 months for hypogonadotropic hypogonadism |
Footnotes for follitropin* Concomitant recombinant follitropin and human chorionic gonadotropin therapy should be continued for at least 3 to 4 months before improvement in spermatogenesis can be expected.
Definitions
For purposes of this policy, the following definitions will be used:
Classification of ovulatory disorders
Anovulation and oligo-ovulation are ovulatory disorders that are estimated to cause 21 % of female fertility problems. The World Health Organization classifies ovulation disorders into 3 groups.
- Group Ihypothalamic pituitary failure (hypothalamic amenorrhea or hypogonadotrophic hypogonadism).
- Group IIhypothalamic pituitary dysfunction (predominately polycystic ovary syndrome).
- Group IIIovarian failure.
Embryo Quality in ART Cycles
An embryo is considered to be of reasonable quality (grade B or its equivalent) if it has less than 50 % fragmentation (see, e.g., Ebner, et al., 2001; Rhenman, et al., 2015; Shaw-Jackson, et al., 2013)..
Fertilization Rates in IVF Cycles
Fertilization rates are considered poor if IVF cycles result in less than 50 % fertilization.
Ovarian Reserve in Response to Gonadotropin Stimulation
Ovarian reserve is considered normal if 3 or more follicles develop and estrogen levels are greater than 500 mIU/ml following ovarian hyperstimulation with gonadotropins. Diminished ovarian reserve is indicated by peak estrogen levels less than 500 mIU/ml or fewer than 3 mature follicles are available at the time of stimulation and retrieval.
Semen Quality and Quantity
Deficits in semen quantity are considered severe if there are less than 10 million total motile sperm (TMS) per ejaculate (unwashed specimen) or less than 3 million total motile sperm (washed specimen) on 2 separate occasions at least 2 weeks apart. TMS is calculated by multiplying the volume of ejaculate by the concentration (million sperm/ml) by the motility (% moving) (Hajder et al, 2016). Deficits in semen quality are considered severe if there are less than 4 % normal forms using Kruger strict morphology. In men who have met the definition of severe male factor infertility with abnormal sperm quality or quantity more than 2 weeks apart in the past; and then had a successful varicocelectomy resulting in normal sperm quality or quantity, ICSI is considered not medically necessary.
Semen Analysis: World Health Organization Reference Values
- pH: 7.2 to 8.0
- Sperm concentration: 16 million spermatozoa per ml or more
- Sperm morphology (percentage of normal forms): 4 % or more
- Semen volume: 1.4 ml or more
- Total motility (percentage of progressive motility and non-progressive motility): 42 % or more motile or 30 % or more with progressive motility
- Total sperm number: 39 million spermatozoa per ejaculate or more
- Immotile sperm percentage: 20 %
- Vitality: 54 % or more live spermatozoa
Source: Björndahl et al, 2022; Chung et al, 2023; Dhumal et al, 2021
Stages of Endometriosis
Surgically, endometriosis can be staged I–IV (Revised Classification of the American Society of Reproductive Medicine). The various stages show these findings:
Stage I (Minimal)
Findings restricted to only superficial lesions and possibly a few filmy adhesions. Minimal disease is characterized by isolated implants and no significant adhesions.Stage II (Mild)
In addition, some deep lesions are present in the cul-de-sac. Mild endometriosis consists of superficial implants that are less than 5 cm in aggregate and are scattered on the peritoneum and ovaries. No significant adhesions are present.Stage III (Moderate)
As above, plus presence of endometriomas on the ovary and more adhesions. Moderate disease exhibits multiple implants, both superficial and deeply invasive. Peritubal and periovarian adhesions may be evident.
Stage IV (Severe)
As above, plus large endometriomas, extensive adhesions. Severe disease is characterized by multiple superficial and deep implants, including large ovarian endometriomas. Filmy and dense adhesions are usually present.Source: Adapted from ASRM, 1997; Schenken, 2025
References
The above policy is based on the following references:
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