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 2nd 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 2nd 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 1st 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.

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:

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