Cervical cerclage in twin pregnancies

The efficacy of emergency cervical cerclage in singleton and twin pregnancies: a systematic review with meta-analysis

OBJECTIVE

An emergency (rescue) cervical cerclage can be offered to pregnant women presenting with dilatation and prolapsed membranes in the second trimester of pregnancy because of cervical insufficiency. This study aimed to investigate the effectiveness of an emergency cerclage in both singleton and twin pregnancies in the prevention of extreme premature birth.

DATA SOURCES

We performed a systematic literature search in PubMed and Embase from inception to June 2022 for transvaginal cervical emergency cerclages.

STUDY ELIGIBILITY CRITERIA

All studies on transvaginal cervical emergency cerclages with at least 5 patients and reporting survival were included.

METHODS

Included studies were assessed for quality and risk of bias with an adjusted Quality In Prognosis Studies tool. Random-effects meta-analyses and meta-regressions were performed for the primary outcome: survival.

RESULTS

Our search yielded 96 studies, incorporating 3239 women, including 14 studies with an expectant management control group, incorporating 746 women. Overall survival after cervical emergency cerclage was 74%, with a fetal survival of 88% and neonatal survival of 90%. Singleton and twin pregnancies showed similar survival, with a pregnancy prolongation of 52 and 37 days and a gestational age at delivery of 30 and 28 weeks, respectively. Meta-regression analyses indicated a significant inverse association between mean gestational age at diagnosis and pregnancy prolongation and no association between dilatation or gestational age at diagnosis and gestational age at delivery. Compared with expectant management, emergency cerclage significantly increased overall survival by 43%, fetal survival by 17% and neonatal survival by 22%, along with a significant pregnancy prolongation of 37 days and reduction in delivery at <28 weeks of gestation of 55%. These effects were more profound in singleton pregnancies than in twin pregnancies.

CONCLUSION

This systematic review indicates that, in pregnancies threatened by extreme premature birth because of cervical insufficiency, emergency cerclage leads to significantly higher survival, accompanied by significant pregnancy prolongation and reduction in delivery at <28 weeks of gestation, compared with expectant management. The mean gestational age at delivery was 30 weeks, independent of dilatation or gestational age at diagnosis. Survival was similar for singleton and twin pregnancies, implying that emergency cerclage should be considered in both.

Ultrasound-Indicated Cerclage in Twin Pregnancies: A Cohort Study

Background

To report the pregnancy and neonatal outcomes in patients with twin pregnancies who underwent ultrasound-indicated cerclage (UIC) and to compare them to patients with singleton pregnancies undergoing the same procedures.

Methods

Patients who underwent UIC between January 2010 and December 2020 at Kangnam Sacred Heart Hospital were reviewed. We compared characteristics, pregnancy, and neonatal outcomes between patients with singleton and twin pregnancies.

Results

A total of 94 women (56 singleton and 38 twin pregnancies) underwent UIC were included. The mean gestational age (GA) at cerclage and preoperative cervical length (CL) were not significantly different. Twin pregnancies were more likely to deliver at earlier median gestations than singletons (singleton, 36 + 1 weeks vs twin, 32 + 6 weeks, and p = 0.004). The frequency of preterm delivery <34 weeks in twin group was higher than in singleton group (15 (26.8%) vs 20 (52.6%) and p =0.016). However, the frequency of preterm delivery <32, <28, and <24 weeks was not significantly different between two groups. Although neonatal weights in singleton pregnancies were heavier than twin pregnancies, neonatal mortality and morbidities were not significantly different between two groups. Among various factors contributing to preterm birth, preoperative CL ≤ 15 mm was independently associated with a higher risk of preterm delivery before 34 weeks. Furthermore, pregnancy and neonatal outcomes of twin pregnancies with cervical length ≤ 15 mm are comparable with those of singleton pregnancies (GA at delivery, singleton, 35 + 1 weeks vs twin, 32 + 5 weeks, and p = 0.24; neonatal mortality, singleton, 3.4% vs twin, 4.8%, and p = 0.64).

Conclusion

The pregnancy and neonatal outcomes of UIC in twin pregnancies were comparable to those in singleton pregnancies, especially when CL is ≤15 mm. UIC might be considered a safe procedure for twin pregnancies.

The impact of cerclage in twin pregnancies on preterm birth rate before 32 weeks

PURPOSE

To evaluate whether cerclage in twins reduces the rate of spontaneous preterm birth <32 weeks when compared to expectant management.

METHODS

This is a retrospective cohort study of twin pregnancies with the following indications for cerclage from two institutions: history of prior preterm birth, ultrasound-identified short cervix ≤2.5 cm, and cervical dilation ≥1.0 cm. The "cerclage" cohort received a cerclage from a single provider at a single institution from 2003-2016. The "no cerclage" group included all patients with similar indications that were expectantly managed from 2010-2015, at a second institution where cerclages are routinely not performed in twin pregnancies. The primary outcome was the rate of spontaneous preterm birth at <32 weeks. Secondary outcomes were the rates of spontaneous and overall (including medically indicated) preterm births at <32 weeks, < 34 weeks, and <36 weeks, chorioamnionitis, birth weight, and neonatal mortality within 30 days of life. We also performed a planned subgroup analysis stratified by cerclage indication.

RESULTS

In all, 135 women were included in two cohorts: cerclage (n = 96) or no cerclage (n = 39). The rates of spontaneous preterm birth <32 weeks were 10.4% (n = 10) with cerclage versus 28.2% (n = 11) without cerclage (OR 0.23, CI 0.08-0.70, p = .017). After adjusting for cerclage indication, clinical history, age, chorionicity, insurance type, race, BMI, in-vitro fertilization, and multifetal reduction, there remained a significant reduction in the cerclage group of spontaneous preterm birth <32 weeks (adjusted odds ratio (aOR) 0.24, CI 0.06-0.90, p = .035), spontaneous preterm birth <36 weeks (aOR 0.34, CI 0.04-0.81, p = .013) as well as in overall preterm birth <32 weeks (aOR 0.31, CI 0.1-0.86, p = .018), and overall preterm birth <36 weeks (aOR 0.37, CI 0.10-0.84, p = .030). When stratified by short cervix or cervical dilation in the cerclage versus no cerclage groups, there was a significant decrease in spontaneous preterm birth <32 weeks in the cerclage group with cervical dilation (11.1 versus 41.2%, p = .01) but not in the cerclage group with short cervix only, even for cervical length <1.5 cm. Pregnancy latency was 91 days in the cerclage group versus 57 days in the no cerclage group (p = .001), with a median gestational age at delivery of 35 versus 32 weeks (p = .002). There was no increase in chorioamnionitis in the cerclage group. Furthermore, there was a significant increase in birth weight (median 2278 versus 1665 g, p < .001) and decrease in perinatal death <30 days (1.6 versus 12.9%, p = .001).

CONCLUSIONS

Cerclage in twin pregnancies significantly decreased the rate of spontaneous preterm birth <32 weeks compared to expectant management. However, when stratified by cerclage indication, this decrease in primary outcome only remained significant in the group with cervical dilation.

Cerclage for women with twin pregnancies: a systematic review and metaanalysis

OBJECTIVE DATA

This study was conducted to estimate whether cerclage could extend the prolongation of pregnancy, reduce the risk of preterm birth, and improve perinatal outcomes in women with twin pregnancies.

STUDY ELIGIBILITY CRITERIA

We included randomized controlled trials and cohort studies comparing the efficacy of cerclage with no cerclage for women with twin pregnancies.

STUDY APPRAISAL AND SYNTHESIS METHODS

The following databases were searched for all published studies that compared cerclage placement with expectant management in twin pregnancies from inception to July 2018: Medline, EMBASE, Scopus, ClinicalTrials.gov, Web of Science, and Cochrane Library. Each report was reviewed for inclusion or exclusion standard, and data extraction was performed by 2 authors independently.

RESULTS

A total of 16 studies with 1211 women that met the inclusion criteria were included in the final analysis. Our outcomes indicated that cerclage placement for twin pregnancies with a cervical length of <15 mm was associated with significant prolongation of pregnancy by a mean difference of 3.89 weeks of gestation (95% confidence interval, 2.19-5.59; P=.000; I²=0%) and a reduction of preterm birth at <37 weeks of gestation (risk ratio, 0.86; 95% confidence interval, 0.74-0.99; P=.040; I²=0%), <34 weeks of gestation (risk ratio, 0.57; 95% confidence interval, 0.43-0.75; P=.000; I²=0%) and <32 weeks of gestation (risk ratio, 0.61; 95% confidence interval, 0.41-0.90; P=.010; I²=0%), compared with those pregnancies in the control group. For women with a dilated cervix of >10 mm, cerclage placement was associated with significant prolongation of pregnancy by a mean difference of 6.78 weeks of gestation (95% confidence interval, 5.32-8.24; P=.000; I²=0%); a reduction of preterm birth at <34 weeks of gestation (risk ratio, 0.56; 95% confidence interval, 0.45-0.69; P=.000; I²=28%), <32 weeks of gestation (risk ratio, 0.50; 95% confidence interval, 0.38-0.65; P=.000; I²=14%), <28 weeks of gestation (risk ratio, 0.41; 95% confidence interval, 0.20-0.85; P=.030; I²=80%), and <24 weeks of gestation (risk ratio, 0.35; 95% confidence interval, 0.18-0.67; P=.001; I²=24%), and improvement of perinatal outcomes compared with those in the control group. However, for twin pregnancies with a normal cervical length (eg, cerclage for an indication for women with a history of preterm birth or twin alone), the efficacy of cerclage placement was less certain because of the limited data.

CONCLUSION

Our metaanalysis indicates that cerclage placement is beneficial for the reduction of preterm birth and the prolongation of pregnancy in twin pregnancies with a cervical length of <15 mm or dilated cervix of >10 mm. However, the benefit of history-indicated or twin alone-indicated cerclage is less certain in twin pregnancies with normal cervical length according to current literature. Further high-quality studies were needed to confirm the findings.

Twin pregnancies treated with emergency or ultrasound-indicated cerclage to prevent preterm births

Introduction: Multiple gestations are high-risk pregnancies associated with an increased risk of neonatal morbidity and mortality, mainly due to preterm births. Numerous interventions have been attempted in order to delay the time of delivery and subsequently, prevent preterm births in twin gestations. To date, no really effective intervention has been found. Use of cerclage in twin pregnancies has been controversial. Recently, however, small retrospective cohort studies have shown a potentially positive effect with the use of cerclage in twin pregnancies. The aim of this study was to evaluate pregnancies and neonatal outcomes in twin gestations with a short cervix treated with cervical cerclage at a single University Hospital.Methods: This retrospective cohort study included all women - with twin gestation and a short cervix - who had an ultrasound indicated or emergency cervical cerclage at the Department of Obstetrics and Gynecology, Aarhus University Hospital, Skejby, Denmark between January 1999 and May 2017. Cervical cerclage was offered to women before 26 weeks of gestation if: (1) the cervix at ultrasound was ≤20 mm without cervical dilatation (ultrasound-indicated cerclage), or (2) the cervix at ultrasound was ≤20 mm with cervical dilatation (emergency cerclage). Women with history-indicated cerclage placement or multifetal embryo reduction were excluded. A total of 65 women participated in the study.Results: The median gestational age at cerclage placement was 22.6 weeks with a median cervical length of 10 mm (range 0-20 mm). The frequency of preterm delivery before 32 weeks of gestation was 41.5% and 27.7% before 28 weeks. Median pregnancy latency was 77 days (range 4-148) and the median gestational age at delivery was 33.0 weeks. Gestational age at delivery was significantly lower among women with cervical dilatation and visible membranes than among women with a short cervix only (27.7 versus 33.6 weeks, p < .01) and so was the median pregnancy latency (48 versus 81 days, p < .05). Overall, neonatal survival was 91.5%.Conclusion: Cervical cerclage in twin pregnancies may prolong pregnancy even when placed on a very short or dilated cervix. In our study, the procedure was safe and without any serious complications. The overall neonatal survival rate was high.

Successful Rescue Cerclage in a Monochorionic Diamniotic Twin Pregnancy at 20 Weeks: Case Report and Overview of Literature

BACKGROUND

In twin pregnancies, elective cerclage placement based on obstetrical history or ultrasound findings has been shown to be ineffective and even harmful. There are currently no guidelines for the use of rescue cervical cerclage in twin pregnancies.

CASE

The current report presents the case of a 33-year-old patient with monochorionic diamniotic twins (MCDA) found to have dilated cervix at 3.5cm with exposed membranes upon physical examination at 19 weeks and 3 days. An emergency McDonald cerclage was placed at 20 weeks and the patient carried the current pregnancy until 35weeks 6 days.

CONCLUSION

Rescue cerclage represents an important option to consider in order to preserve twin pregnancies regardless of chorionicity.

Does cervical cerclage decrease preterm birth in twin pregnancies with a short cervix?

PURPOSE

To determine if use of cerclage in twin gestations with mid-trimester short cervix is associated with decreased preterm birth rate.

STUDY DESIGN

This is a retrospective cohort of twin gestations identified with cervical length of ≤2.5 cm before 24 weeks of gestation through the perinatal ultrasound database of two institutions from 2008 to 2014. Patients with and without cerclage were compared for a primary outcome of preterm birth at <35 weeks. A pre-planned sub-group analysis of patients with cervical length ≤1.5 cm was also performed.

RESULTS

Eighty-two patients were included; 43 received cerclage, 39 did not. Mean gestational age at cerclage placement was 20.8 weeks. There was no significant difference in rate of preterm birth <35 weeks between the groups (34.9% versus 48.7%, respectively). In the sub-group analysis of patients with cervical length ≤1.5 cm, there was a significant decreased risk of preterm birth <35 weeks [37% versus 71.4%; adjusted RR 0.49 (0.26-0.93)].

CONCLUSION

Cerclage placement for cervical length ≤2.5 cm in twin gestations did not decrease the rate of preterm birth at <35 weeks; however, cerclage placement for cervical length ≤1.5 cm was associated with a significantly decreased rate of preterm birth <35 weeks when compared to patients managed without cerclage.

Cervical length at mid-gestation in screening for preterm birth in twin pregnancy

OBJECTIVE

Short cervical length (CL) in mid-gestation is considered predictive of spontaneous preterm birth (PTB). The medical literature suggests 20 mm as the cut-off for high risk in twin pregnancies. Our objective was to assess the predictive value of CL for spontaneous PTB < 32 weeks' gestation in twin pregnancies and to calculate the cut-off point with the best sensitivity and specificity.

METHODS

This was a single-center retrospective cohort study of women in whom CL had been measured by transvaginal ultrasound at 18-23 weeks' gestation. Pregnancies complicated by twin-to-twin transfusion syndrome, those requiring intrauterine therapy or those with indicated PTB were excluded. The predictive value of CL for PTB < 32 weeks was assessed. The distribution of CL measurements and the optimal cut-off in patients with PTB were calculated and logistic regression analysis was performed to assess the association between pregnancy characteristics and PTB.

RESULTS

A total of 940 twin pregnancies were included. CL showed an area under the receiver-operating characteristics curve of 0.65 (95% CI, 0.58-0.71) for the prediction of PTB < 32 weeks. The optimal cut-off value for predicting PTB was 36 mm (sensitivity, 64.1%; specificity, 62.8%; positive predictive value, 13.5%; negative predictive value, 95.1%; accuracy, 62.9%). The relative risk of PTB with CL ≤ 36 mm was 2.35 (95% CI, 1.53-3.60; P < 0.001). After adjusting for confounders in logistic regression analysis, only CL (adjusted odds ratio (aOR), 0.94 (95% CI, 0.90-0.99); P = 0.03), and not monochorionicity (aOR 4.14 (95% CI, 0.89-19.25); P = 0.07), was independently associated with PTB. More than one-third (36%) of PTB cases delivering < 32 weeks had a normal CL in mid-gestation. This proportion rose to 85% when considering the 20-mm cut-off suggested by the medical literature.

CONCLUSIONS

This study shows that, despite the weak independent association, CL assessed in mid-gestation is a poor predictor of PTB < 32 weeks' gestation in asymptomatic twin pregnancies. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Cerclage in twin pregnancy with dilated cervix between 16 to 24 weeks of gestation: retrospective cohort study

BACKGROUND

Cervical dilation in the second trimester is associated with a greater than 90% rate of spontaneous preterm birth and a poor perinatal prognosis.

OBJECTIVE

To compare the perinatal outcomes of twin pregnancies with dilated cervix in women who underwent either cerclage or expectant management.

STUDY DESIGN

Retrospective cohort study of asymptomatic twin pregnancies identified with cervical dilation of ≥1 cm at 16-24 weeks (1997-2014) at 7 institutions. Exclusion criteria were genetic or major fetal anomaly, multifetal reduction at >14 weeks, prior cerclage placement, monochorionic-monoamniotic placentation, active vaginal bleeding, labor, chorioamnionitis, elective termination of pregnancy, or medically indicated preterm birth. The primary outcome was incidence of spontaneous preterm birth at <34 weeks. Secondary outcomes were incidence of spontaneous preterm birth at <32 weeks, <28 weeks, and <24 weeks; perinatal mortality; and composite adverse neonatal outcome (respiratory distress syndrome, intraventricular hemorrhage, necrotizing enterocolitis, and sepsis).

RESULTS

A total of 76 women with twin pregnancy with dilated cervix of 1.0-4.5 cm were managed with either cerclage (n = 38) or expectant management (n = 38). Demographic characteristics were not significantly different. Analysis was adjusted for amniocentesis and vaginal progesterone use. In the cerclage group, 29 women (76%) received prophylactic indomethacin and 36 (94%) received prophylactic antibiotics, whereas the expectant management group did not. Interval from time at diagnosis of open cervix to delivery in the cerclage group was 10.46 ± 5.6 weeks vs 3.7 ± 3.2 weeks in the expectant management group, with a mean difference of 6.76 weeks (95% confidence interval [CI], 4.71-8.81). There were significant decreases in spontaneous preterm birth at <34 weeks (52.6% vs 94.7%; adjusted odds ratio [aOR], 0.06; 95% CI, 0.03-0.34), at <32 weeks (44.7% vs 89.4%; aOR, 0.08; 95% CI, 0.03-0.34); at <28 weeks (31.6% vs 89.4%; aOR, 0.05; 95% CI, 0.01-0.2); and at <24 weeks (13.1% vs 47.3%; aOR, 0.17; 95% CI, 0.05-0.54). There were also significant reductions in perinatal mortality (27.6% vs 59.2%; aOR, 0.24; 95% CI, 0.11-0.5), neonatal intensive care unit admission (75.9% vs 97.6%; aOR, 0.07; 95% CI, 0.01-0.66), and composite adverse neonatal outcome (33.9% vs 90.5%; aOR, 0.05; 95% CI, 0.01-0.21).

CONCLUSION

Cerclage, indomethacin, and antibiotics in twin pregnancies with dilated cervix ≥1 cm before 24 weeks were associated with significant longer latency period from diagnosis to delivery (6.7 weeks), decreased incidence of spontaneous preterm birth at any given gestational age, and improved perinatal outcome when compared with expectant management.

A clinical opinion on how to manage the risk of preterm birth in twins based on literature review

Twin pregnancies are prone to preterm birth and consequent morbidity. There is an increasing evidence base concerning the prediction and prevention of preterm birth in singletons, including the reduction of morbidity with therapies such as magnesium sulphate and antenatal corticosteroids. However, the research in twins is less clear, partly due to fewer numbers being investigated, but also evidence is largely based on twins without a previous history. Prophylactic interventions such as cerclage, progesterone and vaginal pessaries are increasingly showing benefit in singleton pregnancies with a prior history and when the cervix is short. Cerclage in twins has not been adequately researched in women with previous preterm birth, and as with singletons should not be used on the basis of a short cervix alone. Vaginal progesterone does not work in twins, but its value in high-risk twins, with a prior history and short cervix is uncertain. The vaginal pessary may be valuable in the twin with a short cervix. Currently, it is reasonable to extrapolate some of the evidence from singletons to twins, e.g. with antenatal corticosteroids and magnesium sulphate. Cerclage, vaginal pessaries and progesterone should not be routinely used in twin pregnancies without an additional high-risk factor such as prior history of preterm birth or short cervix, until further evidence is obtained.

Rapid cervical phIGFBP-1 test in asymptomatic twin pregnancies: role in mid-pregnancy prediction of spontaneous preterm delivery

Objective This study aimed to assess the accuracy of a second-trimester rapid cervical phosphorylated insulin-like growth factor binding protein-1 (phIGFBP-1) test to predict spontaneous preterm delivery in asymptomatic twin pregnancies. Method During the second trimester, a rapid test to detect phIGFBP-1 in cervical secretions was performed on consecutive twin pregnancies between 2009 and 2011, to evaluate its predictive value for spontaneous preterm delivery at <28, <30, <32 and <34 weeks' gestation. Excluded were patients with cerclage, pessary or undergoing indicated preterm delivery. Results A total of 197 pregnancies fulfilled the study criteria and were tested at a median gestational age of 20.3 weeks (interquartile range: 20-20.6). Median gestational age at delivery was 36.4 weeks. Spontaneous preterm delivery at <34 weeks occurred in 21 (10.7%) cases, at <32 weeks in 9 (4.5%), at <30 weeks in 6 (3%) and at <28 weeks in 4 (2%). Seventeen patients (8.7%) were test positive: In this group, three patients delivered before 34 weeks' gestation, whereas none delivered at <32 weeks. The sensitivity, specificity, positive and negative predictive value of the test for spontaneous preterm delivery <34 weeks were 14% (95% confidence interval, 3-37%), 92% (86-95%), 17% (4-44%) and 90% (84-93%), respectively, with a positive and negative likelihood ratio of 1.79 (0.56-5.74) and 0.93 (0.78-1.10). Conclusions In the second trimester, rapid cervical phIGFBP-1 testing in asymptomatic twin pregnancies has a poor performance in predicting spontaneous preterm delivery.