Cervical Cerclage Performed at 24-32+0 Weeks in Twin Pregnancies: A Multicenter Descriptive Cohort Study

Background and Objectives: Twin pregnancies carry a high risk of preterm birth, and cerclage for a short or dilated cervix is typically placed before 24 weeks. Its use at or after 24 weeks is less well characterized in twins. Materials and Methods: We describe the perinatal course of twin pregnancies that underwent cervical cerclage at 24-32+0 weeks at three university hospitals in South Korea between 2015 and 2024, with pregnancies treated before 24 weeks as a descriptive reference. Entry into the late group required remaining undelivered at 24 weeks without prior cerclage, so the groups do not share a common baseline and were not compared. Results: Eighteen pregnancies received cerclage at 24-32+0 weeks (median 26.3 weeks), and 25 received it before 24 weeks. In the late group, delivery occurred at a median of 34.1 weeks (IQR 31.7-35.4) after a mean cerclage-to-delivery interval of 45.8 days (95% CI 34.7-56.9). No fetal, neonatal, or perinatal death occurred (0 of 36 fetuses in 18 pregnancies; 95% CI 0.0-17.6%, calculated on the 18 pregnancies). NICU admission was 83.3% (95% CI 62.3-93.8), and adverse neonatal morbidity was 55.6% (95% CI 34.2-75.0). Conclusions: No perinatal death was recorded in this descriptive series. Because no untreated control group was available, these findings do not establish efficacy but provide a real-world basis for future prospective controlled trials.