Transabdominal Cerclage

Number: 0529

Policy

Aetna considers transabdominal cerclage medically necessary for the treatment of an incompetent cervix for any of the following conditions:

1. Deep traumatized cervix; or
2. Previous failed cervical (transvaginal) cerclages; or
3. Shortened (less than 2.5 cm) or amputated cervix, or
4. Transabdominal placement of a cervical cerclage for cervical incompetence prior to conception via laparoscopy or laparotomy.

Aetna considers transabdominal cerclage experimental and investigational for all other indications (e.g., prophylactic cerclage for multiple gestations) because of insufficient evidence of effectiveness.

Note: A history consistent with incompetent cervix must be documented to establish the medical necessity of this procedure. This includes a history of mid-trimester pregnancy loss that is associated with painless cervical dilatation without evidence of uterine activity.

Background

Incompetent cervix is a significant cause of second-trimester pregnancy loss.  It is portrayed by gradual, painless dilation of the cervix in the second or third trimester with bulging and rupture of the membranes and subsequent expulsion of a fetus too immature to survive.

Cervical incompetence may be due to previous obstetric or gynecological trauma or a congenital weakness of the cervix (NICE, 2007). The condition is usually diagnosed after one or more late second trimester or early third trimester pregnancy losses, and after other causes have been excluded.

The role of cervical cerclage in the prevention of miscarriage due to cervical incompetence is well established yet remains controversial.  The most commonly employed techniques are performed vaginally and are designed to reinforce the cervix at the level of the internal os.  This involves placing a stitch of strong thread or tape around the cervix, via the vagina, and tightening it to keep the cervix closed. The procedure is typically performed at the end of the first trimester or the beginning of the second trimester, and the stitch is usually removed at around 37 weeks’ gestation (NICE, 2007).

If there is insufficient cervical tissue to allow placement of a cerclage vaginally, a transabdominal approach (either open or laparoscopic) is sometimes used.  With this procedure, an encircling suture is placed above the cardinal and uterosacral ligaments.  Transabdominal cerclage is not frequently performed and is only indicated for those patients with previous failed cervical cerclages, shortened or amputated cervix, and/or deep traumatized cervix.  This procedure should only be performed by physicians with special training and expertise in this procedure.

The clinical value of pre-pregnancy cerclage has not been firmly established.  In a meta-analysis, Drakeley and colleagues (2003) stated that the effectiveness of prophylactic cerclage in preventing preterm delivery in women at low or medium risk for second-trimester pregnancy loss has not been proven.  The role of cerclage in women whose ultrasound reveals short cervix remains uncertain.  Shennan and Jones (2004) stated that elective cerclage is only effective in a minority of women, and the evidence to support its use is limited.  It is currently being evaluated whether indicated cerclage, dictated by ultrasound findings, is beneficial.

The Royal College of Obstetricians and Gynaecologists' guideline on the investigation and treatment of couples with recurrent miscarriage (2003) did not mention the use of pre-pregnancy cerclage.  Furthermore, the American College of Obstetricians and Gynecologists' guideline on cervical insufficiency (2003) stated that elective cerclage can be considered in patients with a history of 3 or more unexplained mid-trimester pregnancy losses or preterm deliveries.  Moreover, cerclage should be performed at 13 to 16 weeks gestation after ultrasound evaluation has shown the presence of a live fetus with no apparent anomalies.

Guidance from the National Institute for Health and Clinical Excellence (2007) stated that the evidence on the safety and efficacy of laparoscopic cerclage for prevention of recurrent pregnancy loss due to cervical incompetence is limited, and therefore this procedure should not be used without special arrangements for consent and for audit or research. The Specialist Advisers to NICE considered this procedure to be novel and expressed uncertainty about its efficacy. They listed key efficacy outcomes of laparoscopic cerclage as live birth rate, ‘take-home baby’ rate, prolongation of pregnancy, reduction in perioperative morbidity and perinatal morbidity, operating times and blood loss. The NICE guidance noted that It was noted that there is uncertainty about the efficacy of all cervical cerclage techniques as a treatment for recurrent loss of pregnancy due to cervical incompetence. The NICE The Committee noted specific concerns about performing the procedure in women who are not pregnant. These include the difficulty in defining the internal os for correct placement of the suture, and ensuring that the suture is not tied in such a way that there is a risk of it cutting through the cervix during subsequent pregnancy.

The American College of Obstetricians and Gynecologists (ACOG)’s practice bulletin on "Cerclage for the management of cervical insufficiency" (ACOG, 2014a) stated that "Transabdominal cervicoisthmic cerclage generally is reserved for patients in whom a cerclage is indicated based on the diagnosis of cervical insufficiency but cannot be placed because of anatomical limitations (e.g., after a trachelectomy), or in the case of failed transvaginal cervical cerclage procedures that resulted in second-trimester pregnancy loss".

Rafael et al (2014) stated that cervical cerclage is a surgical intervention involving placing a stitch around the uterine cervix.  The suture material aims to prevent cervical shortening and opening, thereby reducing the risk of preterm birth.  The effectiveness and safety of this procedure in multiple gestations remains controversial.  In a Cochrane review, these investigators examined if the use of a cervical cerclage in multiple gestations, either at high risk of pregnancy loss based on just the multiple gestation (history-indicated cerclage), the ultrasound findings of "short cervix" (ultrasound-indicated cerclage), or the physical exam changes in the cervix (physical exam-indicated cerclage), improves obstetrical and perinatal outcomes.  The primary outcomes assessed were peri-natal deaths, serious neonatal morbidity, and peri-natal deaths and serious neonatal morbidity.  These investigators searched the Cochrane Pregnancy and Childbirth Group's Trials Register (June 30, 2014) and reference lists of retrieved studies.  All randomized controlled trials (RCTs) of cervical cerclage in multiple pregnancies were selected for review.  Quasi-RCTs and RCTs using a cluster-randomized design were eligible for inclusion (but none was identified).  Studies using a cross-over design and those presented only as abstracts were not eligible for inclusion.  These researchers included studies comparing cervical cerclage with no cervical cerclage in multiple pregnancies.  Studies comparing cervical stitch versus any other preventative therapy (e.g., progesterone) in multiple pregnancies, and studies involving comparisons between different cerclage protocols (history-indicated versus ultrasound-indicated versus physical exam-indicated cerclage) were also eligible for inclusion but none was identified.  Two review authors independently assessed trials for inclusion and risk of bias.  Two review authors extracted data. Data were checked for accuracy.  These researchers included 5 trials, which in total randomized 1,577 women, encompassing both singleton and multiple gestations.  After excluding singletons, the final analysis included 128 women, of which 122 women had twin gestations, and 6 women had triplet gestations.  Two trials (n = 73 women) assessed history-indicated cerclage, while 3 trials (n = 55 women) assessed ultrasound-indicated cerclage.  The 5 trials were judged to be of average to above average quality, with 3 of the trials at unclear risk regarding selection and detection biases.  Concerning the primary outcomes, when outcomes for cerclage were pooled together for all indications and compared with no cerclage, there was no statistically significant differences in peri-natal deaths (19.2 % versus 9.5 %; risk ratio (RR) 1.74, 95 % confidence intervals (CI): 0.92 to 3.28, 5 trials, n = 262), serious neonatal morbidity (15.8 % versus 13.6 %; average RR 0.96, 95 % CI: 0.13 to 7.10, 3 trials, n = 116), or composite perinatal death and neonatal morbidity (40.4 % versus 20.3 %; average RR 1.54, 95 % CI: 0.58 to 4.11, 3 trials, n = 116).  Among the secondary outcomes, there were no significant differences between the cerclage and the no cerclage groups.  To name a few, there were no significant differences among the following: preterm birth less than 34 weeks (average RR 1.16, 95 % CI: 0.44 to 3.06, 4 trials, n = 83), preterm birth less than 35 weeks (average RR 1.11, 95 % CI: 0.58 to 2.14, 4 trials, n = 83), low birth-weight less than 2,500 g (average RR 1.10, 95 % CI: 0.82 to 1.48, 4 trials, n = 172), very low birth-weight less than 1,500 g (average RR 1.42, 95 % CI: 0.52 to 3.85, 4 trials, n = 172), and respiratory distress syndrome (average RR 1.70, 95 % CI: 0.15 to 18.77, 3 trials, n = 116).  There were also no significant differences between the cerclage and no cerclage groups when examining caesarean section (elective and emergency) (RR 1.24, 95 % CI: 0.65 to 2.35, 3 trials, n = 77) and maternal side-effects (RR 3.92, 95 % CI: 0.17 to 88.67, 1 trial, n = 28).  Examining the differences between pre-specified subgroups, ultrasound-indicated cerclage was associated with an increased risk of low birth-weight (average RR 1.39, 95 % CI: 1.06 to 1.83, Tau² = 0.01, I² = 15 %, 3 trials, n = 98), very low birth-weight (average RR 3.31, 95 % CI: 1.58 to 6.91, Tau² = 0, I² = 0 %, 3 trials, n = 98), and respiratory distress syndrome (average RR 5.07, 95 % CI: 1.75 to 14.70, Tau² = 0, I² = 0 %, 3 trials, n = 98).  However, given the low number of trials, as well as substantial heterogeneity and subgroup differences, these data must be interpreted cautiously.  No trials reported on long-term infant neurodevelopmental outcomes.  There were no physical exam-indicated cerclages available for comparison among the studies included.  The authors concluded that the findings of this review were based on limited data from 5 small studies of average to above average quality.  They stated that for multiple gestations, there is no evidence that cerclage is an effective intervention for preventing preterm births and reducing perinatal deaths or neonatal morbidity.

The ACOG’s practice bulletin on "Multifetal gestations: Twin, triplet, and higher-order multifetal pregnancies" (ACOG, 2014b) stated that "Interventions, such as prophylactic cerclage, prophylactic tocolytics, prophylactic pessary, routine hospitalization, and bed rest, have not been proved to decrease neonatal morbidity or mortality and, therefore, should not be used in women with multifetal gestations".

Saccone et al (2015) evaluated the effectiveness of cerclage for preventing preterm birth in twin pregnancies with a short cervical length (CL).  Searches were performed in electronic databases. These investigators performed an individual patient data meta-analysis of randomized trials of twin pregnancies screened by trans-vaginal ultrasound in second trimester and where mothers had a short CL less than 2.5 cm before 24 weeks.  Eligible women had to be randomized to cerclage versus no-cerclage (control).  The primary outcome was preterm birth less than 34 weeks.  A total of 3 trials with 49 twin gestations with a short CL were identified.  All original databases for each included trial were obtained from the primary authors.  Risk factors were similar in the cerclage and control groups, except that previous preterm birth was more frequent and gestational age at randomization and delivery were earlier in the cerclage group compared with the control group.  Adjusting for previous preterm birth and gestational age at randomization, there were no statistically significant differences in primary (adjusted odds ratio [OR] 1.17, 95 % CI: 0.23 to 3.79) and secondary outcomes.  Rates of very low birth-weight and of respiratory distress syndrome were significantly higher in the cerclage group than in the control group.  The authors concluded that based on these Level 1 data, cerclage cannot currently be recommended for clinical use in twin pregnancies with a maternal short CL in the second trimester.  They stated that large trials are still needed.

Song et al (2015) examined pregnancy outcome following trans-abdominal cerclage (TAC) in women with cervical insufficiency (CI) and explored parameters for predicting pregnancy outcomes following TAC.  In this retrospective cohort study, these investigators included 161 women with TAC.  They considered demographic, obstetric, and gynecologic histories, pre- and post-operative CL, and CL at 20 to 24 weeks as parameters for predicting outcomes following TAC.  Uni-variate and multi-variate analyses were used to identify risk factors for predicting delivery before 34 weeks after TAC.  A total of 182 pregnancies occurred after TAC, and 290 pregnancies prior to TAC were identified.  The rate of delivery less than 34 weeks significantly decreased following TAC (5 % versus 82 %, p < 0.001).  Uni-variate analysis demonstrated that a short CL (less than 2.5 cm) at 20 to 24 weeks and adenomyosis were associated with delivery at less than 34 weeks' gestation following TAC (p = 0.015 and p = 0.005, respectively).  However, multi-variate analysis demonstrated that only a short CL (less than 2.5 cm) at 20 to 24 weeks was a significant predictor (p = 0.005).  The authors concluded that TAC is an effective procedure that prolongs pregnancy in women with CI.  A short CL at 20 to 24 weeks may predict the delivery at less than 34 weeks' gestation following TAC.

Groom et al (2004) conducted a study to report pregnancy outcome and complication rates for women with recurrent late pregnancy loss who were treated with preconception transabdominal cervicoisthmic cerclage. They implemented a case note review of 19 women who were treated with preconception transabdominal cervicoisthmic cerclage at Queen Charlotte's and Chelsea Hospital from 1994 to 2003 and were at high risk for second trimester loss and early preterm delivery. The results showed that preconception transabdominal cervicoisthmic cerclage was associated with a postoperative fetal survival rate of 100% for pregnancies that reached >12 weeks of gestation, compared with a preoperative fetal survival rate of 12%. No significant intraoperative, antenatal, intrapartum or neonatal complications were reported. The investigators concluded that within this case series preconception transabdominal cervicoisthmic  cerclage was a safe alternative to transabdominal cervicoisthmic cerclage that was performed in pregnancy with no risk to a fetus.

Tulandi et al (2014) conducted a study to evaluate the efficacy of abdominal cerclage via laparoscopy vs laparotomy. The evaluation was conducted both before vs after conception. The investigators evaluated 16 studies published between 1990 and 2013 involving a total of 678 cases in which abdominal cerclage was studied. A generalized linear model was used to estimate the effect of laparotomy over laparoscopy and the effect of preconceptional over postconceptional cerclage by treating the success rates (third trimester delivery and live birth) as dependent variables and laparotomy and preconceptional as independent factors. The results showed no difference in the rates of third-trimester delivery and live birth rates between preconceptional abdominal cerclage via laparoscopy (71.4%-83.3% and 90%-100%, respectively) or laparotomy (97.3%-100% and 100%, respectively). In cases of postconceptional cerclage, the rates of third-trimester delivery and live birth via laparoscopy were 70% and 70% to 100%, respectively, and via laparotomy were 77.4% to 99.5% and 85.2% to 100%, respectively. Performing abdominal cerclage before or during pregnancy resulted in no difference in the live birth rates. The authors concluded that the rates of third-trimester delivery and live birth after abdominal cerclage via laparoscopy are high and comparable to those via laparotomy. They further noted that the efficacy of the procedure performed either before or during pregnancy is similar, although abdominal cerclage performed before conception is more practical than after conception. In particular when performed in non-pregnant women, there is an inherent advantage of laparoscopy over laparotomy. Thus, laparoscopy is preferable in non-pregnant women.

An UpToDate report on transabdominal cervical cerclage states that "Transabdominal cerclage placement can be performed prior to conception or in early pregnancy. Preconception placement provides optimum exposure and reduces risks of excessive bleeding and injury to the pregnancy. Placement of the cerclage after the first trimester is undesirable since the large size of the uterus makes the procedure difficult and thus may be associated with a higher risk of complications. No randomized trials have compared outcomes with preconception versus postconception cerclage. A review of 14 studies of abdominal cerclage published between 1990 and 2013 and involving a total of 678 patients reported live birth rates were similar whether abdominal cerclage was performed before or during pregnancy."

Dawood and Farquharson (2016) stated that TAC is an effective intervention to prevent spontaneous mid-trimester loss and preterm delivery when a trans-vaginal cerclage has failed.  A TAC may be inserted during the first trimester (T1) of pregnancy or pre-conceptually.  In a retrospective and prospective cohort study, these investigators determined whether or not pre-conceptual (PC) TAC confers any benefit over T1 TAC insertion in terms of associated surgical and pregnancy-related morbidity and subsequent pregnancy outcome.  This study included 161 consecutive women who underwent PC TAC versus T1 TAC over a 22-year period from January 1993 to January 2015 at a tertiary referral miscarriage clinic.  Data were obtained from case note review retrospectively from 1993 to 2006 and prospectively between 2006 and 2015.  Inclusion criteria comprised a history of at least 1 previous spontaneous mid-trimester loss coupled with at least 1 failed trans-vaginal cerclage and screening for anti-phospholipid syndrome and bacterial vaginosis.  Of 144 patients who conceived, 121 had complete pregnancy outcomes; 62 in the PC group and 59 in the T1 group.  Both groups had similar previous pregnancy losses and previous trans-vaginal cerclage history.  Successful pregnancies of greater than 24 weeks occurred in 97 % of PC TACs compared to 93 % in the T1 group.  Furthermore, a successful pregnancy of greater than 34 weeks occurred in 90 % (56/62) in the PC group compared to 74 % (44/59) in the T1 group (OR 3.18; CI: 1.14 to 8.8).  Significantly fewer patients needed emergency caesarean section for preterm delivery in the PC group (7/62 (12 %) versus 21/59 (36 %); OR 4.34; CI: 1.68 to 11.32).  All 6 failures before 24 weeks gestation (T1 = 4, PC = 2) were associated with anti-phospholipid syndrome or bacterial vaginosis.  In the T1 group 3/65 (5 %) of patients suffered serious surgical complications and hemorrhage of 500 mls occurred in 32/65 (50 %) of cases whereas no surgical complications occurred in the PC group.  The authors concluded that PCTAC was more successful in preventing repeat spontaneous mid-trimester loss and preterm labor, and was associated with less surgical and pregnancy-related morbidity compared to T1 TAC insertion.

Transabdominal Cerclage for Cervical Insufficiency in Multiple Gestations

Debieve and colleagues (2020) noted that the diagnosis of cervical insufficiency is based on the previous history of recurrent second or early third trimester losses.  Its incidence among pregnant women is 0.5 to 1 % but can be as high as 75 % among women with pre-term birth.  Transvaginal cerclage (TVC) is the common therapy of cervical insufficiency.  However, this technique has several limits, especially in twin pregnancies.  As some selected conditions, a TAC is indicated, it has been offered to patients with multiple pregnancies.  These investigators examined the outcomes of twin pregnancies with TAC in terms of pre-term birth rate and neonatal morbidity and mortality.  They conducted a retrospective study of 7 patients with twin pregnancies managed with TAC at the end of the first trimester (12 to 15 weeks).  These researchers selected patients with a history of fetal loss who met the indications criteria of TAC (history of TVC failure or short cervix unable to have TVC).  The ante-natal and delivery data were collected and compared to those of their previous pregnancy.  All patients carried their pregnancy throughout the second trimester and delivered during the third trimester.  Mean gestational age was 34 4/7 weeks.  All newborns were alive and neonatal morbidity rate was 50 %, mostly related to pre-term birth.  Mean duration of neonatal intensive care stay was 32 days.  There were no operative complications following TAC.  The authors concluded that perinatal outcomes were considerably improved in twin pregnancies with TAC.  These researchers stated that their findings corroborated with those of previous case reports and supported the efficacy of TAC for managing cervical insufficiency in twin pregnancies.

On the other hand, an UpToDate review on "Cervical insufficiency" (Berghella, 2019) states that "For women with twin or higher-order multiple pregnancies, we suggest avoiding cerclage".

Also, an UpToDate review on "Twin pregnancy: Prenatal issues" (Chasen and Chervenak, 2019) lists cerclage as a potential intervention.  It states that "A 2014 systematic review of randomized trials comparing cervical cerclage with no cervical cerclage in multiple gestations did not provide convincing evidence that cerclage is an effective intervention for preventing preterm birth and reducing perinatal death or neonatal morbidity.  Because of the small number of pregnancies in the review, a modest effect cannot be excluded (122 twin pregnancies and 6 triplet pregnancies; cerclage was indicated by obstetric history in 2 trials [n = 73 pregnancies] and transvaginal ultrasound in 3 trials [n = 55 pregnancies]).  None of the randomized trials in this review included women with physical examination-indicated cerclage".

Furthermore, an UpToDate review on "Triplet Pregnancy," (Hayes, 2019) considers prophylactic cerclage as an unproven intervention. It states that "Prophylactic cerclage (defined as a cerclage placed only because of triplet pregnancy) in women without a history of cervical insufficiency does not appear to prolong gestation or improve neonatal outcomes.  In the rare clinical scenario of a woman who has a history of cervical insufficiency and is now carrying triplets, we still do not perform a history-indicated cerclage since there is no proven benefit and studies have suggested possible harm in multiples with cerclage.  We strongly recommend consideration of multifetal pregnancy reduction in these cases".

Preconception Laparoscopic Transabdominal Cervical Cerclage

Saridogan and colleagues (2019) stated that a recent Cochrane review concluded that cervical cerclage reduced preterm birth before 37, 34 and 28 weeks of gestation and also probably reduced the risk of perinatal death.  Transabdominal cerclage was developed for a subgroup in whom TVC had failed or was not possible.  This approach appeared more effective in improving fetal survival rates or obstetric outcomes. Most commonly transabdominal cervical cerclage is placed at laparotomy (open TAC), but with the advance of minimal access techniques, laparoscopic transabdominal cervical cerclage is replacing the traditional open operation.  In a prospective, case-series study, these researchers examined the outcomes of pre-conception laparoscopic TAC procedures.  Data were prospectively collected from 54 women at high risk of second trimester miscarriage and pre-term delivery due to cervical insufficiency undergoing pre-conception laparoscopic TAC by a single operator.  This included demographics, obstetric and gynecological history (including previous cervical cerclage procedures), surgical complication rates, conception and subsequent pregnancy outcomes.  There were 36 pregnancies progressing beyond the first trimester with a "take home baby" rate of 89 % (32/36), a live-birth rate of 92 % (33/36) and neonatal survival rate of 97 % (32/33). The mid-trimester loss (MTL) rate was 8 % (3/36) with delivery rates after 37 weeks of 75 % (27/36) and between 34 to 37 weeks of 8 % (3/36) and 23 to 34 weeks of 8 % (3/36).  The authors concluded that this prospective, case-series study provided further evidence that laparoscopic TAC was feasible, safe and effective when TVC failed or was not possible.  Moreover, these researchers stated that comparative studies are likely to be difficult, but prospective data collection and development of national or international registries are likely to produce further evidence on its use for wider indications.

The main drawbacks of this study were its relatively small sample size (n = 54), and the lack of a control group, especially for those who had not been pregnant before.  It would be difficult to randomize women with a history of failed TVC, however, it may be possible to collect data from women who chose to have expectant management instead of laparoscopic TAC following cervical surgery causing absent ectocervix or short cervix.

Cervical Cerclage in Combination with Other Treatments for Prevention of Spontaneous Preterm Birth

Eleje and colleagues (2020) noted that pre-term birth (PTB) remains the foremost global cause of peri-natal morbidity and mortality; therefore, the prevention of spontaneous PTB still remains of critical importance.  In an attempt to prevent PTB in singleton pregnancies, cervical cerclage, in combination with other treatments, has been advocated.  This is because, cervical cerclage is an intervention that is commonly recommended in women with a short cervix at high risk of PTB but, despite this, many women still deliver prematurely, as the biological mechanism is incompletely understood.  Furthermore, previous Cochrane Reviews have been published on the effectiveness of cervical cerclage in singleton and multiple pregnancies; however, none has examined the effectiveness of using cervical cerclage in combination with other treatments.  In a Cochrane review, these researchers examined if antibiotics administration, vaginal pessary, reinforcing or second cerclage placement, tocolytic, progesterone, or other interventions at the time of cervical cerclage placement would prolong singleton gestation in women at high risk of pregnancy loss based on prior history and/or ultrasound (US) finding of “short cervix” and/or physical examination.  History-indicated cerclage is defined as a cerclage placed usually between 12- and 15-week of gestation based solely on poor prior obstetrical history, e.g., multiple 2nd trimester losses due to painless dilatation.  Ultrasound-indicated cerclage was defined as a cerclage placed usually between 16- and 23-week of gestation for transvaginal US (TVUS) cervical length of less than 20 mm in a woman without cervical dilatation.  Physical examination-indicated cerclage was defined as a cerclage placed usually between 16- and 23-week of gestation because of cervical dilatation of 1 or more cm detected on physical (manual) examination.  These investigators searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) (September 26, 2019), and reference lists of retrieved studies.  They included published, unpublished or ongoing randomized controlled trials (RCTs).  Studies using a cluster-RCT design were also eligible for inclusion in this review; however, none was identified.  These researchers excluded quasi-RCTs (e.g., those randomized by date of birth or hospital number) and studies using a cross-over design.  These investigators also excluded studies that specified addition of the combination therapy after cervical cerclage because the woman subsequently became symptomatic.  They included studies comparing cervical cerclage in combination with 1, 2 or more interventions with cervical cerclage alone in singleton pregnancies.  Two review authors independently screened titles and abstracts of all retrieved articles, selected studies for inclusion, extracted data, assessed risk of bias, and evaluated the certainty of the evidence for this review's main outcomes.  Data were checked for accuracy; standard Cochrane review methods were used throughout.

These researchers identified 2 studies (involving a total of 73 women) comparing cervical cerclage alone to a different comparator.  They also identified 3 ongoing studies (1 examining vaginal progesterone after cerclage, and 2 examining cerclage plus pessary).  One study (n = 20 women), conducted in the United Kingdom, comparing cervical cerclage in combination with a tocolytic (salbutamol) with cervical cerclage alone in women with singleton pregnancy did not provide any useable data for this review.  The other study (with data from 50 women) took place in the United States and compared cervical cerclage in combination with a tocolytic (indomethacin) and antibiotics (cefazolin or clindamycin) versus cervical cerclage alone.  This study did provide useable data for this review (and the study authors also provided additional data on request) but meta-analyses were not possible.  This study was generally at a low risk of bias, apart from issues relating to blinding.  These investigators downgraded the certainty of evidence for serious risk of bias and imprecision (few subjects, few events and wide 95 % CI).  Cervical cerclage in combination with an antibiotic and tocolytic versus cervical cerclage alone (1 study, 50 women/babies).  These researchers were unclear regarding the effect of cervical cerclage in combination with antibiotics and a tocolytic compared with cervical cerclage alone on the risk of serious neonatal morbidity (RR 0.62, 95 % CI: 0.31 to 1.24; very low-certainty evidence); peri-natal loss (data for miscarriage and stillbirth only – data not available for neonatal death) (RR 0.46, 95 % CI: 0.13 to 1.64; very low-certainty evidence) or PTB of less than 34 completed weeks of pregnancy (RR 0.78, 95 % CI: 0.44 to 1.40; very low-certainty evidence).  There were no stillbirths (intra-uterine death at 24 or more weeks).  The trial authors did not report on the numbers of babies discharged home healthy (without obvious pathology) or on the risk of neonatal death.  The authors concluded that there is insufficient evidence to examine the effect of combining a tocolytic (indomethacin) and antibiotics (cefazolin/clindamycin) with cervical cerclage compared with cervical cerclage alone for preventing spontaneous PTB in women with singleton pregnancies.  Future studies should recruit sufficient numbers of women to provide meaningful results and should measure neonatal death and numbers of babies discharged home healthy, as well as other important outcomes listed in pared the effectiveness of laparoscopic and open TAC in patients suffering with CI.  These investigators performed literature searches that included PubMed, Scopus, Medline, ClinicalTrials.Gov, Cochrane and Web of Science.  They analyzed the data with Open Meta-Analyst Software as well as Review Manager Software.  These researchers included observational and RCTs that included patients with CI who underwent laparoscopic cerclage or TAC.  These investigators included a total of 43 studies.  Laparoscopic and TAC had a positive effect by increasing gestational age (GA); for the laparoscopic group (mean deviation (MD)) = 14.86 weeks (W), 95 % CI: 10.67 to 19.05, p < 0.001) and TAC (MD = 12.79 W, 95 % CI: 10.97 to 14.61, p < 0.001).  Furthermore, improvements in all outcomes assessed (total fetal survival rate, neonatal weight, and prevention of de livery at a GA of less than 24 weeks) were all significant with the exception of the prevention of all PTDs of less than 37 weeks; for both laparoscopic at (RR = 0.116, 95 % CI: -0.006 to 0.238, p = 0.063) and TAC at (MD = 1, 95 % CI: 0.45 to 2.24, p = 1), and for prevention of deliveries of less than 34 weeks for the laparoscopic group (RR = 0.446, 95 % CI: -0.323 to 1.215, p = 0.256) only.  The authors concluded that although limited data prevented pregnancy and pre-pregnancy subgroups as well as a head-to-head comparison, these investigators still found that in patients suffering from CI, both TAC and laparoscopic approaches to cerclage revealed a positive effect in preserving the pregnancy.

Sunami et al (2022) examined the usefulness of modified trans-abdominal cervico-isthmic cerclage (TAC) using mono-filament thread for the prevention of PTD in women with an extremely short cervix after deep conization.  These researchers devised a mono-filament thread for picking up the seromuscular layer of the site that is slightly cephalad to the internal ostium to prevent injury of the vessels around the uterine cervix.  From 2017 to 2020, these investigators performed this modified operation in 8 women (9 pregnancies) at 12 to 16 weeks of gestation with a history of deep cervical conization.  A modified TAC was successfully performed in all patients.  There was no measurable bleeding, and all patients were discharged without post-operative complications.  Their pregnancy courses after the operation were uneventful.  Of 9 pregnancies, 1 patient had premature uterine contractions and underwent cesarean section at 36 weeks (PTD).  In the other 8 pregnancies, planned cesarean section was performed after 37 weeks of gestation.  The median birth weight of the babies was 2,996 g (range of 2,604 to 3,374 g).  All patients were discharged on the 6th post-operative day without complications.  The authors concluded that a modified TAC could be safely carried out and may prolong pregnancy without adverse events (AEs) in patients with an extremely short cervix.

Zhao et al (2022) stated that CI is a major cause of 2nd-trimester pregnancy loss and spontaneous PTD; TAC is usually carried out prior to pregnancy for patients of CI, in whom trans-vaginal cervical cerclage procedure cannot be placed or has failed previously.  Performing a TAC becomes a huge challenge owing to the enlargement of the pregnant uterus in patients who were indicated for TAC but were missed before pregnancy.  These investigators outlined an easy and effective surgical procedure as needle-free laparoscopic trans-broad-ligament cervico-isthmic cerclage during early 2nd-trimester.  Laparoscope with 4 trocars was established, after expanding the trigonum of ureter, ovarian vascular and ascending branch of uterine artery.  The needleless Mersilene tape was inserted in a posterior-to-anterior direction of bilateral trigonums, tightening the knot toward the bladder uterine reflection and simultaneously pushing the loop behind the uterus, directed to the cervix progressively.  The tape was then tied anteriorly at the cervico-isthmic junction with 5 to 6 intracorporeal square knots after transvaginal US determined the presence of systolic velocity of uterine artery with first knot.  The primary feature of this procedure was that the needleless Mersilene tape was inserted centrally from the broad ligaments, lateral to the uterine vessels, and finally tied above the uterosacral ligament at the level of the uterine isthmus, without dissecting the bladder off from lower uterine segment and without separating the uterine vessels from the lateral wall of the cervix.  The authors performed this procedure on 10 patients with pregnancy outcomes and there was no pregnancy loss.  This procedure proved to be an accessible and effective surgical technique for TAC of the uterine cervix during early 2nd trimester, with affirmative prognosis.

Table: CPT Codes/ HCPCS Codes / ICD-10 Codes

Code	Code Description
Information in the [brackets] below has been added for clarification purposes.   Codes requiring a 7th character are represented by "+":
CPT codes covered if selection criteria are met:
57700	Cerclage of uterine cervix, nonobstetrical [cervical incompetence prior to conception]
59325	Cerclage of cervix, during pregnancy; abdominal
ICD-10 codes covered if selection criteria are met:
N88.3	Incompetence of cervix uteri
O34.30 - O34.33	Maternal care for cervical incompetence
O34.40 - O34.43	Maternal care for other abnormalities of cervix [shortened, amputated, or deep traumatized cervix]
ICD-10 codes not covered for indications listed in the CPB:
O30.001 - O30.93	Multiple gestation

The above policy is based on the following references: