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 pre -senting with dilatation and prolapsed membranes in the second trimester of pregnancy because of cervical insufficiency. This study aimed to investigate the effectiveness of an emer-gency 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 Qual-ity In Prognosis Studies tool. Random-effects meta-analyses and meta-regressions were per -formed 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.