To estimate the effectiveness of physical examination–indicated cerclage in the setting of second-trimester cervical dilatation by systematic review and meta-analysis of published studies.
We searched MEDLINE, EMBASE, Scopus, ClinicalTrials.gov, Web of Science, and the Cochrane Library for studies published between 1966 and 2014 that evaluated cervical cerclage for the treatment of cervical insufficiency.
METHODS OF STUDY SELECTION:
The search yielded 6,314 citations. We included cohort studies and randomized controlled trials comparing cerclage placement with expectant management of women with cervical dilatation between 14 and 27 weeks of gestation. Two investigators independently reviewed each citation for inclusion or exclusion and discordant decisions were arbitrated by a third reviewer. Summary estimates were reported as the mean difference and 95% confidence interval (CI) for continuous variables or relative risk and with 95% CI for dichotomous outcomes. Fixed- and random-effects meta-analysis was used, depending on heterogeneity.
TABULATION, INTEGRATION, AND RESULTS:
Ten studies met inclusion criteria and were included in the final analysis. One was a randomized controlled trial, two were prospective cohort studies, and the remaining seven were retrospective cohort studies. Of the 757 women, 485 (64%) underwent physical examination–indicated cerclage placement and 272 (36%) were expectantly managed. Cerclage was associated with increased neonatal survival (71% compared with 43%; relative risk 1.65, 95% CI 1.19–2.28) and prolongation of pregnancy (mean difference 33.98 days, 95% CI 17.88–50.08).
Physical examination–indicated cerclage is associated with a significant increase in neonatal survival and prolongation of pregnancy of approximately 1 month when compared with no such cerclage. The strength of this conclusion is limited by the potential for bias in the included studies.