Emergency cerclage in singleton pregnancies with painless cervical dilatation: A meta-analysis

Emergency cerclage is the most common active intervention in pregnant women with cervical insufficiency. This meta-analysis aimed to compare the effectiveness of emergency cerclage vs expectant management on maternal and perinatal outcomes, and to assess the current status of evidence.

A search was conducted from 1 June 2019 until 1 September 2019 and eligible studies were identified in the MEDLINE, Scopus, Cochrane and US clinical trials registry without limitations concerning the publication dates and languages. Randomized controlled trials (RCTs), non-RCTs and observational studies comparing emergency cerclage with no cerclage/expectant management, in women presenting with painless cervical dilatation were included.

The electronic search yielded 3607 potential studies, of which 38 were fully reviewed and 12 observational studies (1021 participants) were included. Cerclage was superior to expectant management for the primary outcomes of preterm birth before 28 and 32 gestational weeks, OR 0.25 (95% CI 0.16-0.39, five studies, N = 392, I² = 41%, low quality) and 0.08 (95% CI 0.02-0.29, four studies, N = 176, I² = 51%, low quality), respectively. Cerclage was also superior to expectant management for the secondary outcomes of fetal loss OR 0.26 (95% CI 0.12-0.56, 8 studies, N = 455, I² = 46%, very low-quality), pregnancy prolongation in days mean difference 47.45 (95% CI 39.89-55.0, 12 studies, N = 1027 I² = 86%, very low quality), gestational age at birth in weeks mean difference 5.68 (95% CI 4.69-6.67, 9 studies, N = 892, I² = 73%, very low quality), admission to neonatal intensive care OR 0.21 (95% CI 0.07-0.70, two studies, N = 79, I² = 36%, very low quality) and neonatal death OR 0.12 (95% CI 0.04-0.34, five studies, N = 130, I² = 0%, very low quality). There were no differences between cerclage and expectant management concerning premature rupture of membranes during or after the procedure OR 0.68 (95% CI 0.31-1.48, two studies, N = 155, I² = 85%, very low quality) and chorioamnionitis OR 1.14 (95% CI 0.31-4.25, three studies, N = 88, I² = 33%, very low quality).

Emergency cerclage in pregnant women with painless cervical dilatation seems to decrease preterm births, prolong the pregnancy, and decrease the neonatal deaths and fetal losses, but does not increase the risk of chorioamnionitis and premature rupture of membranes. Despite the extremely favorable estimates for cerclage, the results should be viewed with caution because, as a result of the lack of randomized control trials, the quality of evidence is low to very low.