Depo-Provera (Injectable Medroxyprogesterone Acetate):

1. Aetna considers Depo-Provera (medroxyprogesterone acetate injectable suspension) medically necessary for any of the following indications:

   1. Breast cancer
   2. Cystic ovaries
   3. Dysfunctional uterine bleeding
   4. Dysmenorrhea
   5. Endometrial cancer
   6. Endometriosis
   7. Menorrhagia
   8. Oligomenorrhea
   9. Renal cancer

2. Aetna considers Depo-Provera medically necessary for the prevention of pregnancy. Note: Many plans exclude coverage of contraceptives.  Please check benefit plan descriptions for details.

3. Aetna considers Depo-Provera experimental and investigational for all other indications because its effectiveness for these indications has not been established.

Lunelle (Combination Estrogen and Medroxyprogesterone Injection):

Aetna considers Lunelle (combination of estrogen and medroxyprogesterone in a monthly contraceptive injection) medically necessary for prevention of pregnancy.

Aetna considers Lunelle experimental and investigational for all other indications because its effectiveness other than the one listed above has not been established.  Note: Many plans exclude coverage of contraceptives.  Please check benefit plan descriptions for details.

Makena (17-alpha Hydroxyprogesterone Caproate) Injection:

Note: REQUIRES PRECERTIFICATION*

Aetna considers 17-alpha hydroxyprogesterone caproate injection medically necessary for the prevention of preterm birth (defined as delivery at less than 37 weeks, 0 days gestation) in women who are pregnant with a singleton pregnancy and have history of a prior spontaneous preterm birth of a singleton delivery.  Consistent with FDA-approved labeling, Makena must be initiated between 16 weeks, 0 days and 20 weeks, 6 days of gestation and should continue thought 37 weeks, 0 days gestation (see Appendix).  Also consistent with FDA-approved labeling, Makena is considered experimental and investigational for all other indications including multiple gestation, known fetal anomaly, cervical insufficiency/incompetent cervix, women with a cerclage in place, as a toclytic agent for women with contractions, or other risk factors for preterm birth because its effectiveness for these indications has not been established.  Makena is considered experimental and investigational for persons with the following contraindications to its use: 1) current or history of thrombosis or thromboembolic disorders; 2) known or suspected breast cancer, other hormone-sensitive cancer, or history of these conditions; 3) undiagnosed abnormal vaginal bleeding unrelated to pregnancy; 4) cholestatic jaundice of pregnancy; 5) liver tumors, benign or malignant, or active liver disease; and 6) uncontrolled hypertension.

 *Note: Precertification of Makena is required of all Aetna participating providers and members in applicable plan designs.  For precertification of Makena, call (866) 503-0857, or fax (866) 267-3277.

Progesterone Injection:

Aetna considers progesterone injection medically necessary for any of the following indications:

1. Corpus luteum insufficiency (Note: Coverage is limited to persons with Advanced Reproductive Technology benefits covering injectable medications for infertility); or
2. Diagnosis of endogenous estrogen production (as in diagnosis of menopause); or
3. Menstrual disorders including secondary amenorrhea and dysfunctional uterine bleeding.

Aetna considers progesterone injection experimental and investigational for all other indications, including any of the the following, because it has not been shown to be effective for these indications:

1. Prevention of pregnancy; or
2. Redution of neonatal morbidity/prolongation of pregnancy in twin pregnancies,; or
3. Treatment of endometrial hyperplasia; or
4. Treatment of premenstrual syndrome.

Etonogestrel Subdermal Implant:

Aetna considers etonogestrel subdermal implant (Implanon) medically necessary for the prevention of pregnancy. 

Aetna considers etonogestrel subdermal implant experimental and investigational for all other indications because its effectiveness other than the one listed above has not been established.  Note: Many plans exclude coverage of contraceptives.  Please check benefit plan descriptions for details. 

Progestin-Releasing Intrauterine Devices:

Aetna considers progestin-releasing intrauterine devices (IUDs) (e.g., Mirena levonorgestrel-releasing IUD; Progestasert progesterone-releasing IUD; Skyla levonorgestrel-releasing IUD) medically necessary for contraception and for treatment of heavy menstrual bleeding. 

Aetna considers progestin-releasing IUDs experimental and investigational for all other indications (e.g., treatment of uterine fibroids) because its effectiveness for indications other than the ones listed above has not been established.  Note: Many plans exclude coverage of contraceptives.  Please check benefit plan descriptions for details.

Progesterone Vaginal Suppositories:

Aetna considers progesterone vaginal suppositories medically necessary for infertility associated with documented ovarian failure, supplementation of endogenous progesterone in women at high-risk of spontaneous abortion due to documented luteal phase deficiency, and for pregnant women with a singleton pregnancy and prior history of preterm delivery before 37 weeks gestation or short cervical length (less than 20 mm).

Aetna considers progesterone vaginal suppositories experimental and investigational for the reduction of the risk of preterm delivery in high-risk twin pregnancies, treatment of pre-menstrual syndrome (PMS)/pre-menstrual dysphoric disorder (PMDD), and for all other indications because its effectiveness for these indications has not been established.

See also CPB 0327 - Infertility, CPB 0468 - Terbutaline Pump for Preterm Labor, and CPB 0512 - Premenstrual Syndrome and Premenstrual Dysphoric Disorder.

Depo-Provera is an injectable formulation of medroxyprogesterone acetate, a derivative of progesterone.  Depo-Provera has shown efficacy for the adjunctive and palliative treatment of advanced, inoperable endometrial or renal carcinoma.  Additionally, as an intramuscular injection administered every 3 months, Depo-Provera has been shown to be highly effective in the prevention of pregnancy (less than 1 % failure rate in the first year).  It is also effective in treating other various progesterone-mediated conditions.

When being used as a contraceptive, Depo-Provera is only covered under plans that specifically cover contraceptive drugs (without specifying oral contraceptives), contraceptive devices, or contraceptive drug implants.

Intramuscular medroxyprogesterone has been used for the treatment of menorrhagia/abnormal uterine bleeding, as an alternative to oral progestogen therapy.  However, since progestogen therapy for menorrhagia/abnormal uterine bleeding must be cyclical in nature, experts usually prescribe oral, rather than intramuscular, medroxyprogesterone for these indications.

Parenteral medroxyprogesterone has been used as an alternative to oral forms of medroxyprogesterone when indicated to treat breast carcinoma in post-menopausal women; however, recognized drug compendia note that only parenteral medroxyprogesterone is indicated for adjunct treatment of metastatic renal or endometrial carcinoma and endometriosis.

Parenteral medroxyprogesterone was used in the past as a treatment for precocious puberty, but has been replaced by other modalities.

The U.S. Pharmacopoeia (2002) stated that, although oral medroxyprogesterone is preferred, parenteral medroxyprogesterone has been used for secondary amenorrhea, dysmenorrhea, menorrhagia, oligomenorrhea, dysfunctional uterine bleeding, endometriosis, and endometrial hyperplasia accompanying polycystic ovary syndrome.

According to recognized drug compendia, oral therapy is preferred for female hormone replacement in menopause and for testing for endogenous estrogen production.

Lunelle (combination estrogen and medroxyprogesterone injection) was approved by the Food and Drug Administration (FDA) as a once per month injectable contraceptive in October 1999.  Lunelle was not approved by the FDA for any indication other than the prevention of pregnancy.

Norplant (levonorgestrel) is an implantable, combined drug and delivery system that continuously releases a low-dose of the progestin levonorgestrel.  Norplant is FDA approved for contraception and is surgically implanted in the physicians' office or clinic.  A single implant provides contraception for up to 5 years.  Norplant is especially useful for patients for whom compliance is an issue, and for patients for whom pregnancy poses an unacceptable medical risk.  It is recommended that a trial of a progestin-only oral contraceptive be carried out prior to implantation, to assess patient tolerance to drug side effects.  Norplant (levonorgestrel subdermal implant) is no longer available in the United States.

On July 17, 2006, Implanon (Organon USA, Inc., Roseland, NJ), a single-rod progestogen-only (etonogestrel) contraceptive implant, received FDA approval.  Implanon is the only implantable contraceptive device currently available in the United States.  The distribution of Norplant was stopped in 2000 after questions surfaced about the strength of certain lots of the drug.  In 2002, Wyeth Pharmaceuticals (Madison, NJ), the manufacture of Norplant, decided not to re-introduce Norplant to the U.S. market.

Implanon is a long-acting (up to 3 years), reversible, contraceptive method.  It must be removed by the end of the 3rd year and may be replaced by a new Implanon at the time of removal if continued contraceptive protection is desired.  Implanon is contraindicated in women who have (i) known or suspected pregnancy, (ii) current or past history of thrombosis or thromboembolic disorders, (iii) hepatic tumors (benign or malignant), active liver disease, (iv) undiagnosed abnormal genital bleeding, (v) known or suspected carcinoma of the breast or personal history of breast cancer, and (vi) hypersensitivity to any of the components of Implanon.

In a multi-center clinical study, Funk and colleagues (2005) evaluated the safety and effectiveness of Implanon.  Sexually active American women (n = 330) with apparently normal menstrual cycles used the implant for up to 2 years.  All subjects recorded bleeding and/or spotting daily in a diary.  Safety was assessed through adverse experiences (AE), laboratory tests and physical and gynecological examinations.  Total exposure was 474 woman-years (6,186 cycles), and 68 % of subjects had at least 1 year of exposure.  No pregnancies occurred.  The most common bleeding pattern observed throughout the study was infrequent bleeding, defined as less than 3 episodes of bleeding in a reference period (excluding amenorrhea).  The least common pattern was frequent bleeding, defined as more than 5 episodes of bleeding in a reference period.  Infrequent, prolonged and frequent bleeding patterns were most common early in the study and declined thereafter.  During the 3-month reference periods 2 to 8 (months 4 to 24), the incidence of amenorrhea ranged from 14 to 20 %.  A total of 43 subjects (13 %) withdrew from the study because of bleeding pattern changes and 76 subjects (23 %) discontinued because of other AE.  Other common AE leading to discontinuation, besides bleeding irregularities, were emotional lability (6.1 %), weight increase (3.3 %), depression (2.4 %) and acne (1.5 %).  Use of Implanon for up to 2 years had no clinically significant effects on laboratory parameters, physical and pelvic examinations, vital signs or body mass index.  The average length of time required for Implanon insertion and that for removal were 0.5 and 3.5 mins, respectively, and all the procedures were uncomplicated.  The return to normal menstrual cycles and fertility was rapid after removal.  The authors concluded that Implanon is a safe, highly effective and rapidly reversible new method of contraception.  This finding is in agreement with that of Croxatto (2000) as well as that of Zheng et al (1999).

According to the U.S. Pharmacopoeial Convention (2002), accepted indications for injectable progesterone and hydroxyprogesterone include: (i) treatment of menstrual disorders including secondary amenorrhea and dysfunctional uterine bleeding; (ii) corpus luteum insufficiency treatment; and (iii) diagnosis of endogenous estrogen production.  The U.S. Pharmacopoeia states that progesterone or hydroxyprogesterone injection can be used to test for endogenous estrogen production and can be used to determine whether low levels of estrogen are present if withdrawal bleeding does not occur after a progestin challenge in menopausal women before estrogen-progestin ovarian hormone therapy is considered.  The U.S. Pharmacopoeia notes, however, that determination that serum gonadotropins are elevated is the standard way to confirm menopause.  The U.S. Pharmacopoeial Convention has concluded that injectable progesterone and hydroxyprogesterone has not been shown to be an effective treatment for premenstrual syndrome.  Injectable progesterone or hydroxyprogesterone is not indicated for prevention of pregnancy.

de Fonseca et al (2003) reported on the results of a randomized, placebo-controlled trial of progestin vaginal suppositories in high-risk women, and found that the incidence of preterm birth was significantly reduced, from 28.5 % to 13.8 % for births before 37 weeks, and from 18.6 % to 2.8 % for births before 34 weeks in the placebo versus the progesterone groups, respectively.  More recently, Meis et al (2003) reported the results of a multi-center randomized clinical study, involving over 450 high risk women, showed that weekly injections of 17-alpha-hydroxyprogesterone resulted in a significant reduction in recurrent preterm birth.

In a randomized, double-blind, placebo-controlled trial, Rouse et al (2007) examined if 17 alpha-hydroxyprogesterone caproate (17P) would reduce the rate of preterm birth in twin gestations.  Healthy women with twin gestations were assigned to weekly intramuscular injections of 250 mg of 17P or matching placebo, starting at 16 to 20 weeks of gestation and ending at 35 weeks.  The primary study outcome was delivery or fetal death before 35 weeks of gestation.  A total of 661 women were randomly assigned to treatment.  Baseline demographic data were similar in the 2 study groups.  Six women were lost to follow-up; data from 655 were analyzed (325 in the 17P group and 330 in the placebo group).  Delivery or fetal death before 35 weeks occurred in 41.5 % of pregnancies in the 17P group and 37.3 % of those in the placebo group (relative risk, 1.1; 95 % confidence interval [CI]: 0.9 to 1.3).  The rate of the pre-specified composite outcome of serious adverse fetal or neonatal events was 20.2 % in the 17P group and 18.0 % in the placebo group (relative risk, 1.1; 95 % CI: 0.9 to 1.5).  Side effects of the injections were frequent in both groups, occurring in 65.9 % and 64.4 % of subjects, respectively (p = 0.69), but were generally mild and limited to the injection site.  The authors concluded that treatment with 17P did not reduce the rate of preterm birth in women with twin gestations.

In a randomized study, Abu-Musa et al (2008) examined the effect of 17-alpha-hydroxyprogesterone caproate (HPC) before embryo transfer on the outcome of in-vitro fertilization and embryo transfer (IVF-ET).  A total of 125 patients undergoing IVF-ET were randomly assigned into treatment and control groups.  In the treatment group, 63 patients received 17-HPC (250 mg, i.m.), 1 day before ET.  The control group consisted of 62 patients who did not receive any injections.  Main outcome measures were pregnancy and multiple-pregnancy rates.  The 2 groups were similar with respect to the age of patients, total dose of follicle-stimulating hormone, number of oocytes and embryos obtained, and number and quality of embryos transferred.  There was no significant difference in the pregnancy rate (34.9 % versus 38.7 %) or in the rate of multiple gestation (15.9 % versus 9.7 %) between cases and controls, respectively.  The authors concluded that the use of 17-HPC before ET does not appear to affect the outcome of IVF-ET.

Fonesca and colleagues (2007) noted that previous randomized trials have shown that progesterone administration in women who previously delivered prematurely reduces the risk of recurrent premature delivery.  Asymptomatic women found at mid-gestation to have a short cervix are at greatly increased risk for spontaneous early preterm delivery.  These investigators examined if progesterone reduces this risk in such women.  Cervical length was measured by transvaginal ultrasonography at a median of 22 weeks of gestation (range of 20 to 25 weeks) in 24,620 pregnant women seen for routine prenatal care.  Cervical length was 15 mm or less in 413 of the women (1.7 %), and 250 (60.5 %) of these 413 women were randomly assigned to receive vaginal progesterone (200 mg each night) or placebo from 24 to 34 weeks of gestation.  The primary outcome was spontaneous delivery before 34 weeks.  Spontaneous delivery before 34 weeks of gestation was less frequent in the progesterone group than in the placebo group (19.2 % versus 34.4 %; relative risk, 0.56; 95 % CI: 0.36 to 0.86).  Progesterone was associated with a non-significant reduction in neonatal morbidity (8.1 % versus 13.8 %; relative risk, 0.59; 95 % CI: 0.26 to 1.25; p = 0.17).  There were no serious adverse events associated with the use of progesterone.  The authors concluded that in women with a short cervix, treatment with progesterone reduces the rate of spontaneous early preterm delivery.

Simhan and Caritis (2007) stated that although the use of progestational agents to prevent preterm birth among high-risk women is promising, the results of afore-mentioned trials highlight the gaps in the current knowledge of the biologic contribution of various risk factors to preterm birth.  Unanswered questions regarding the possible mechanisms of action of the various progestins in preventing preterm birth have led to uncertainty with respect to choice of agent, route of administration, dose regimen, and clinical indication.  The authors stated that further research on progestational agents is needed.

In an editorial that accompanied the studies by Rouse et al and Fonesca et al, Thornton (2007) stated that there are at least 14 ongoing trials involving women with high-risk pregnancies (both singleton and twin) that aim to recruit a total of more than 5,000 women and the author was aware of at least 2 more currently awaiting funding decisions.  These studies should have ample power to test the effect of progesterone on important fetal outcomes as well as any differential effect in twin gestations, and long-term follow-up of the surviving children will provide important additional information.  In the meantime, the remaining uncertainties about both efficacy and fetal safety mean that even women at high-risk for preterm delivery should join one of the ongoing randomized trials, rather than take a treatment for which the efficacy and safety have not been proved.

In a randomized, double-blind, placebo-controlled study and meta-analysis, Norman et al (2009) examined the use of progesterone for prevention of preterm birth in twin pregnancy.  A total of 500 women with twin pregnancy were recruited from 9 United Kingdom National Health Service clinics specializing in the management of twin pregnancy.  Women were randomized, by permuted blocks of randomly mixed sizes, either to daily vaginal progesterone gel 90 mg (n = 250) or to placebo gel (n = 250) for 10 weeks from 24 weeks' gestation.  All study personnel and participants were masked to treatment assignment for the duration of the study.  The primary outcome was delivery or intra-uterine death before 34 weeks' gestation.  Analysis was by intention-to-treat.  Additionally these investigators undertook a meta-analysis of published and unpublished data to establish the efficacy of progesterone in prevention of early (less than 34 weeks' gestation) preterm birth or intra-uterine death in women with twin pregnancy.  Three participants in each group were lost to follow-up, leaving 247 analysed per group.  The combined proportion of intra-uterine death or delivery before 34 weeks of pregnancy was 24.7 % (61/247) in the progesterone group and 19.4 % (48/247) in the placebo group (odds ratio [OR] 1.36, 95 % CI: 0.89 to 2.09; p = 0.16).  The rate of adverse events did not differ between the 2 groups.  The meta-analysis confirmed that progesterone does not prevent early preterm birth in women with twin pregnancy (pooled OR 1.16, 95 % CI: 0.89 to 1.51).  The authors concluded that progesterone, administered vaginally, does not prevent preterm birth in women with twin pregnancy.

In a Cochrane review, Su and colleagues (2010) examined if the use of progestational agents is effective as a form of treatment or co-treatment for women with threatened or established preterm labor with intact membranes.  These investigators searched the Cochrane Pregnancy and Childbirth Group's Trials Register (March 2009), CENTRAL (The Cochrane Library 2009, Issue 1), MEDLINE (1966 to January 2009) and EMBASE (1974 to January 2009).  They checked references of articles and communicated with authors and pharmaceutical industry.  Randomized controlled trials that compared progestational agents, given either alone or in combination with other tocolytics, with a control group receiving another tocolytic, placebo or no treatment, for the treatment of preterm labor were selected.  Two review authors independently extracted data and assessed trial quality.  There were some data suggesting that the use of progestational agent resulted in a reduction of preterm deliveries at less than 37 weeks of gestation.  The use of progestational agent may also attenuate the shortening of cervical length and reduce the frequency of uterine contractions.  However, the analysis was limited by the small number of available studies.  This review included 4 studies; however, the number of participants in each included study ranged from 35 to 60, which limits the power of the meta-analysis.  The authors concluded that there is currently insufficient evidence to advocate progestational agents as a tocolytic agents for women presenting with preterm labor.

In a multi-center, double-blind, placebo-controlled randomized trial, Lim et al (2011) estimated if administration of 17α-hydroxyprogesterone caproate can prevent neonatal morbidity in multiple pregnancies by reducing the preterm birth rate.  Women with a multiple pregnancy were randomized to weekly injections of either 250 mg 17α-hydroxyprogesterone caproate or placebo, starting between 16 and 20 weeks of gestation and continuing until 36 weeks of gestation.  The main outcome measure was adverse neonatal outcome.  Secondary outcome measures were gestational age at delivery and delivery before 28, 32, and 37 weeks of gestation.  A total of 671 women were randomized.  A composite measure of adverse neonatal outcome was present in 110 children (16 %) born to mothers in the 17α-hydroxyprogesterone caproate group, and in 80 children (12 %) of mothers in the placebo group (relative risk [RR] 1.34; 95 % CI: 0.95 to 1.89).  The mean gestational age at delivery was 35.4 weeks for the 17α-hydroxyprogesterone caproate group and 35.7 weeks for the placebo group (p = 0.32).  Treatment with 17α-hydroxyprogesterone caproate did not reduce the delivery rate before 28 weeks (6 % in the 17α-hydroxyprogesterone caproate group compared with 5 % in the placebo group, RR 1.04; 95 % CI: 0.56 to 1.94), 32 weeks (14 % compared with 10 %, RR 1.37; 95 % CI: 0.91 to 2.05), or 37 weeks of gestation (55 % compared with 50 %, RR 1.11; 95 % CI: 0.97 to 1.28).  The authors conclued that 17α-hydroxyprogesterone caproate does not prevent neonatal morbidity or preterm birth in multiple pregnancies.

Progestin-releasing intrauterine systems (e.g., Mirena levonorgestrel-releasing intrauterine system; Progestasert progesterone-releasing intrauterine device) are safe, effective, long-term contraceptive devices.  Progestasert offers pregnancy prevention for one year, and Mirena offers pregnancy prevention for 5 years.  Progestin-releasing intrauterine systems have also been shown to decrease the volume of menstrual blood loss in women with normal periods and those with menorrhagia.  Heavy menstrual bleeding markedly impairs the quality of life in many healthy women.  Management of the condition usually depends on the degree of bleeding and discomfort found acceptable by the individual woman.  Medical treatments include oral medications and a hormone-releasing intrauterine system (e.g., Mirena, Progestasert).  Surgical options include conservative surgery (e.g., uterine resection or ablation) and hysterectomy.  A Cochrane review (Marjoribanks et al, 2003) compared the safety, effectiveness, and acceptability of surgery versus medical therapy for heavy menstrual bleeding.  The authors concluded that surgery reduces menstrual bleeding at one year more than medical treatments, but a hormone-releasing intrauterine system appears equally beneficial in improving quality of life and may control bleeding as effectively as conservative surgery over the long-term.

Kuanitz et al (2009) compared the effects of the levonorgestrel intrauterine system and endometrial ablation in reducing heavy menstrual bleeding.  This systematic review and meta-analysis was restricted to randomized controlled trials in which menstrual blood loss was reported using pictorial blood loss assessment chart scores.  A total of 6 randomized controlled trials that included 390 women (levonorgestrel intrauterine system, n = 196; endometrial ablation, n = 194) were retrieved.  Three studies pertained to 1st-generation endometrial ablation (manual hysteroscopy) and 3 to 2nd-generation endometrial ablation (thermal balloon).  Study characteristics and quality were recorded for each study.  Data on the effect of treatment on pictorial blood loss assessment chart scores were abstracted, integrated with meta-analysis techniques, and presented as weighted mean differences.  Both treatment modalities were associated with similar reductions in menstrual blood loss after 6 months (weighted mean difference, -31.96 pictorial blood loss assessment chart score [95 % CI: -65.96 to 2.04]), 12 months (weighted mean difference, 7.45 pictorial blood loss assessment chart score [95 % CI: -12.37 to 27.26]), and 24 months (weighted mean difference, -26.70 pictorial blood loss assessment chart score [95 % CI: -78.54 to 25.15]).  In addition, both treatments were generally associated with similar improvements in quality of life in 5 studies that reported this as an outcome.  No major complications occurred with either treatment modality in these small trials.  The author concluded that based on the meta-analysis of 6 randomized clinical trials, the efficacy of the levonorgestrel intrauterine system in the management of heavy menstrual bleeding appears to have similar therapeutic effects to that of endometrial ablation up to 2 years after treatment.

A number of double-blind clinical trials have failed to show that progesterone suppositories are more effective than placebo in treating premenstrual syndrome.  Although proponents of progesterone therapy for PMS have agreed that many of the clinical trials have been done inappropriately with respect to selection criteria, study size, treatment duration and/or blinding method, at least one study has controlled these variables quite well (Maddocks, 1986).  This study indicated that the response to progesterone vaginal suppositories is, at best, marginal and not significantly different from response to placebo.  Freeman (2004) stated that progesterone has consistently failed to show efficacy for severe PMS/premenstrual dysphoric disorder in large, randomized, placebo-controlled trials.

Although not proven effective, progesterone has also been used during first few months of pregnancy to prevent habitual or threatened abortion due to hormonal imbalance but may also delay expulsion of a defective ovum.  Potter and Scott (2005) stated that inadequate progesterone production has been proposed a cause of recurrent pregnancy loss and progesterone is given to prevent miscarriage, despite a lack of supportive evidence.

In a Cochrane review on prenatal administration of progesterone for preventing preterm birth, Dodd et al (2006) noted that intramuscular progesterone is associated with a reduction in the risk of preterm birth of less than 37 weeks' gestation, and infant birth weight of less than 2500 grams.  However, other important maternal and infant outcomes have been poorly reported to date, with most outcomes reported from a single trial only.  It is unclear if the prolongation of gestation translates into improved maternal and longer-term infant health outcomes.  Similarly, information regarding the potential harms of progesterone therapy to prevent preterm birth is limited.  The authors concluded that further information is needed to ascertain the clinical value of the use of vaginal progesterone in the prevention of preterm birth.  Guidelines from the American College of Obstetricians and Gynecologists (2003) have stated that whether vaginal progestins are as effective as intramuscular progestins in preventing preterm birth “remains to be proved in a larger population.”

The American College of Obstetricians and Gynecologists (2008) has stated that "progesterone supplementation for the prevention of recurrent preterm birth should be offered to women with a singleton pregnancy and prior spontaneous preterm birth due to spontaneous preterm labor or premature rupture of membranes. ... Progesterone supplementation for asymptomatic women with an incidentally identified very short cervical length (less than 15 mm) may be considered; however, routine cervical length screening is not recommended."

Rode et al (2009) provided an update on the preventive effect of progesterone on preterm birth in singleton pregnancies.  A search in the PubMed, Embase, and Cochrane database was performed using the keywords: pregnancy, progesterone, preterm birth/preterm delivery, preterm labor, controlled trial, and randomized controlled trial.  Studies on singleton pregnancies were selected.  A meta-analysis was performed on randomized trials including singleton pregnancies with previous preterm birth.  Two new randomized controlled trials of women with previous preterm birth were added to the 4 analyzed in the Cochrane review, and the meta-analysis of all 6 studies now showed that progesterone supplementation was associated with a significant reduction of delivery before 32 weeks and of perinatal mortality.  Furthermore, a 3rd trial showed a positive effect on women with a short cervix at 23 weeks, and a 4th study showed that progesterone reduces the risk of preterm delivery in women with preterm labor.  The authors concluded that in women with a singleton pregnancy and previous preterm delivery, progesterone reduces the rates of preterm delivery before 32 weeks, perinatal death, as well as respiratory distress syndrome and necrotizing enterocolitis in the newborn.  Women with a short cervix or preterm labor may also benefit from progesterone, but further evidence is needed to support such a recommendation.  Follow-up studies should focus on possible metabolic complications in the mother or the offspring.

Cahill et al (2010) estimated which strategy is the most cost-effective for the prevention of preterm birth and associated morbidity.  These investigators used decision-analytic and cost-effectiveness analyses to estimate which of 4 strategies was superior based on quality-adjusted life-years, cost in US dollars, and number of preterm births prevented.  Universal sonographic screening for cervical length and treatment with vaginal progesterone was the most cost-effective strategy and was the dominant choice over the 3 alternatives: cervical length screening for women at increased risk for preterm birth and treatment with vaginal progesterone; risk-based treatment with 17 alpha-hydroxyprogesterone caproate (17-OHP-C) without screening; no screening or treatment.  Universal screening represented savings of $1,339 ($8,325 versus $9,664), when compared with treatment with 17-OHP-C, and led to a reduction of 95,920 preterm births annually in the United States.  The authors concluded that universal sonographic screening for short cervical length and treatment with vaginal progesterone appears to be cost-effective and yields the greatest reduction in preterm birth at less than 34 weeks' gestation.

In a multi-center, randomized, double-blind, placebo-controlled study, Hassan and associates (2011) examined the safety and effectiveness of using micronized vaginal progesterone gel to reduce the risk of preterm birth and associated neonatal complications in women with a sonographic short cervix.  Asymptomatic women with a singleton pregnancy and a sonographic short cervix (10 to 20 mm) at 19 + 0 to 23 + 6 weeks of gestation were enrolled in this study.  They were allocated randomly to receive vaginal progesterone gel or placebo daily starting from 20 to 23 + 6 weeks until 36 + 6 weeks, rupture of membranes or delivery, whichever occurred first.  Randomization sequence was stratified by center and history of a previous preterm birth.  The primary endpoint was preterm birth before 33 weeks of gestation.  Analysis was by intention- to-treat.  Of 465 women randomized, 7 were lost to follow-up and 458 (vaginal progesterone gel, n = 235; placebo, n = 223) were included in the analysis.  Women allocated to receive vaginal progesterone had a lower rate of preterm birth before 33 weeks than did those allocated to placebo (8.9 % (n = 21) versus 16.1 % (n = 36); RR, 0.55; 95 % CI: 0.33 to 0.92; p = 0.02).  The effect remained significant after adjustment for co-variables (adjusted RR, 0.52; 95 % CI: 0.31 to 0.91; p = 0.02).  Vaginal progesterone was also associated with a significant reduction in the rate of preterm birth before 28 weeks (5.1 % versus 10.3 %; RR, 0.50; 95 % CI: 0.25 to 0.97; p = 0.04) and 35 weeks (14.5 % versus 23.3 %; RR, 0.62; 95 % CI: 0.42 to 0.92; p = 0.02), respiratory distress syndrome (3.0 % versus 7.6 %; RR, 0.39; 95 % CI: 0.17 to 0.92; p = 0.03), any neonatal morbidity or mortality event (7.7 % versus 13.5 %; RR, 0.57; 95 % CI: 0.33 to 0.99; p = 0.04) and birth weight less than 1,500 g (6.4 % (15/234) versus 13.6 % (30/220); RR, 0.47; 95 % CI: 0.26 to 0.85; p = 0.01).  There were no differences in the incidence of treatment-related adverse events between the groups.  The authors concluded that administration of vaginal progesterone gel to women with a sonographic short cervix in the mid-trimester is associated with a 45 % reduction in the rate of preterm birth before 33 weeks of gestation and with improved neonatal outcome.

Klein and colleagues (2011) noted that progesterone treatment reduces the risk of preterm delivery in high-risk singleton pregnancies.  These researchers evaluated the preventive effect of vaginal progesterone in high-risk twins.  This was a sub-analysis of a Danish-Austrian, double-blind, placebo-controlled, randomized trial (PREDICT study), in which women with twin pregnancies were randomized to daily treatment with progesterone or placebo pessaries from 20 to 24 weeks until 34 weeks' gestation.  This subpopulation consisted of high-risk pregnancies, defined by the finding of cervical length less than or equal to 10th centile at 20 to 24 weeks' gestation or history of either spontaneous delivery before 34 weeks or miscarriage after 12 weeks.  Primary outcome was delivery before 34 weeks.  Secondary outcomes were complications for infants including long-term follow-up by Ages and Stages Questionnaire (ASQ) at 6 and 18 months of age.  In 72 (10.6 %) of the 677 women participating in the PREDICT study, the pregnancy was considered to be high-risk, including 47 with cervical length less than or equal to 10th centile, 28 with a history of preterm delivery or late miscarriage and 3 fulfilling both criteria.  Baseline characteristics for progesterone and placebo groups were similar.  Mean gestational age at delivery did not differ significantly between the 2 groups either in patients with a short cervix (34.3 +/- 4.1 versus 34.5 +/- 3.0 weeks, p = 0.87) or in those with a history of preterm delivery or late miscarriage (34.6 +/- 4.2 versus 35.2 +/- 2.7 weeks, p = 0.62).  Similarly, there were no significant differences between the treatment groups in maternal or neonatal complications and mean ASQ score at 6 and 18 months of age.  The authors concluded that in high-risk twin pregnancies, progesterone treatment does not significantly improve outcome.

In a double-blind, randomized, clinical trial, Combs et al (2011) examined if prophylactic treatment with 17-alpha-hydroxyprogesterone caproate (17Pc) in twin pregnancy will reduce neonatal morbidity (primary outcome) by prolonging pregnancy (secondary outcome).  Mothers carrying dichorionic-diamniotic twins were randomly assigned (in a 2:1 ratio) to weekly injections of 250 mg of 17Pc or placebo, starting at 16 to 24 weeks and continued until 34 weeks.  In all, 160 women were randomized to 17Pc and 80 to placebo.  Composite neonatal morbidity occurred with similar frequency in the 17Pc and placebo groups (14 % versus 12 %, respectively, p = 0.62).  Mean gestational age at delivery was not affected by 17Pc (35.3 versus 35.9 weeks, p = 0.10), but a 3-day difference in median gestational age favored placebo (p = 0 0.02).  There were no perinatal deaths with 17Pc and 3 with placebo.  The authors concluded that in twin pregnancy, prophylactic treatment with 17Pc did not prolong gestation or reduce neonatal morbidity.

The Society for Maternal-Fetal Medicine Publications Committee (2012) sought to provide evidence-based guidelines for using progestogens for the prevention of preterm birth (PTB).  Relevant documents, in particular randomized trials, were identified using PubMed (U.S. National Library of Medicine, 1983 through February 2012) publications, written in English, which evaluate the effectiveness of progestogens for prevention of PTB.  Progestogens evaluated were, in particular, vaginal progesterone and 17Pc.  Additionally, the Cochrane Library, organizational guidelines, and studies identified through review of the above were utilized to identify relevant articles.  Data were evaluated according to population studied, with separate analyses for singleton versus multiple gestations, prior PTB, or short trans-vaginal ultrasound cervical length (CL), and combinations of these factors.  Consistent with U.S. Preventive Task Force suggestions, references were evaluated for quality based on the highest level of evidence, and recommendations were graded.  Summary of randomized studies indicates that in women with singleton gestations, no prior PTB, and short CL less than or equal to 20 mm at less than or equal to 24 weeks, vaginal progesterone, either 90-mg gel or 200-mg suppository, is associated with reduction in PTB and perinatal morbidity and mortality, and can be offered in these cases.  The issue of universal CL screening of singleton gestations without prior PTB for the prevention of PTB remains an object of debate.  CL screening in singleton gestations without prior PTB can not yet be universally mandated.  Nonetheless, implementation of such a screening strategy can be viewed as reasonable, and can be considered by individual practitioners, following strict guidelines.  In singleton gestations with prior PTB 20 to 36 6/7 weeks, 17Pc 250 mg intra-muscularly weekly, preferably starting at 16 to 20 weeks until 36 weeks, is recommended.  In these women with prior PTB, if the trans-vaginal ultrasound CL shortens to less than 25 mm at less than 24 weeks, cervical cerclage may be offered.  Progestogens have not been associated with prevention of PTB in women who have in the current pregnancy multiple gestations, preterm labor, or preterm premature rupture of membranes.  There is insufficient evidence to recommend the use of progestogens in women with any of these risk factors, with or without a short CL.

On January 9, 2013, the FDA approved Skyla IUD, a new levonorgestrel-releasing intrauterine system, for the prevention of pregnancy for up to 3 years. 

In a Cochrane review, Sangkomkamhang et al (2013) determined the effectiveness of progestogens or progestogen-releasing intrauterine systems in treating pre-menopausal women with uterine fibroids.  These investigators searched the Menstrual Disorders and Subfertility Group Specialized Register (inception to August 17, 2012), CENTRAL (inception to August 17, 2012) and Database of Abstracts of Reviews of Effects (DARE) in The Cochrane Library, MEDLINE (inception to 1August 17, 2012), Ovid EMBASE (January 1, 2010 to August 17, 2012), Ovid PsycINFO (inception to August 17, 2012), CINAHL database, and trials registers for ongoing and registered trials.  All identified published or unpublished randomized controlled trials (RCTs) assessing the effect of progestogens or progestogen-releasing intrauterine systems in treating pre-menopausal women with uterine fibroids.  These researchers assessed all potentially eligible studies identified as a result of the search strategy.  Two review authors extracted data from each included study using an agreed form and assessed the risk of bias.  They resolved discrepancies through discussion.  This review included 3 studies.  However, data for progestogen-releasing intrauterine systems were available from only 1 study that compared 29 women with a levonorgestrel (LNG)-IUS versus 29 women with a combined oral contraceptive (COC) for treating uterine fibroids.  There was a significant reduction of menstrual blood loss (MBL) in women receiving the LNG-IUS compared to the COC using the alkaline hematin test (mean difference (MD) 77.5 %, 95 % CI: 71.3 % to 83.67 %, 58 women) and a pictorial assessment chart (PBAC) (MD 34.5 %, 95 % CI: 14.9 % to 54.1 %, 58 women).  The reduction in uterine fibroid size was significantly greater in the leuprorelin group at 16 weeks compared to the progestogen lynestrenol group (MD -15.93 mm, 95 % CI: -18.02 to -13.84 mm, 46 women).  There was no RCT evaluating the effect of DMPA on uterine fibroids.  The authors concluded that progestogen-releasing intrauterine systems appear to reduce menstrual blood loss in pre-menopausal women with uterine fibroids.  Oral progestogens did not reduce fibroid size or fibroid-related symptoms.  However, there was a methodological limitation and the one included study with data had a small sample size.  They stated that this evidence is insufficient to support the use of progestogens or progestogen-releasing intrauterine systems in treating pre-menopausal women with uterine fibroids.

Appendix

Dosing of Makena

• Makena is administered intra-muscularly at a dose of 250 mg (1 ml) once-weekly.
• Treatment is initiated between 16 weeks, 0 days and 20 weeks, 6 days of gestation.
• Administration is continued once-weekly until week 37 (through 36 weeks, 6 days) of gestation or delivery, whichever occurs first.

Source: Makena Prescribing Information, 2010.