Efficacy of Combined Cervical Cerclage and Vaginal Progesterone for Reducing Preterm Birth

Preterm birth is a significant concern in obstetric care; both vaginal progesterone and cervical cerclage have been identified as effective interventions for its prevention. However, it remains unclear whether combining these therapies would offer superior efficacy compared to using each treatment individually. 

The goal of a new study was to determine the efficacy of combining cervical cerclage and vaginal progesterone in preventing preterm birth.

This study entailed a comprehensive search through multiple databases, including – Medline, EMBASE, PsycINFO, CINAHL, Cochrane Library, and Scopus––from inception until 2020. Randomized and pseudorandomized control trials, nonrandomized experimental control trials, and cohort studies were selected. High-risk patients with shortened cervical length (<25mm) or previous preterm birth who were assigned cervical cerclage, vaginal progesterone, or both for preterm birth prevention were included. Only singleton pregnancies were considered for assessment.

The primary outcome assessed was preterm birth – before 37 weeks of gestation. Secondary outcomes included birth before 28 weeks, 32 weeks, and 34 weeks of gestation, gestational age at delivery, the time interval between intervention and delivery, preterm premature rupture of membranes, cesarean delivery, neonatal mortality, neonatal intensive care unit (NICU) admission, intubation, and birth-weight. The risk of bias and the quality of evidence were evaluated.

Overall, 11 studies were included in the final analysis. The results showed that combined therapy of cervical cerclage and vaginal progesterone lowered the risk of preterm birth before 37 weeks compared to using cerclage alone or progesterone alone. Moreover, the combined therapy also demonstrated benefits in reducing preterm birth before 34, 32, and 28 weeks, reducing neonatal mortality, increasing birthweight, extending gestational age, and prolonging the interval between intervention and delivery. No significant differences were observed in other secondary outcomes.

The systematic review and meta-analysis suggested that combining cervical cerclage and vaginal progesterone is more effective in reducing the rate of preterm birth than using either treatment alone––in women with a short cervix or a history of preterm birth. The combined therapy significantly reduced preterm birth rates at various gestational weeks. However, further well-conducted and adequately powered randomized controlled trials are needed to validate and establish the robustness of these promising findings.

Source: Aubin AM, McAuliffe L, Williams K, et al. American journal of obstetrics & gynecology MFM. 2023 May 20:101024.