Factors Associated With Pregnancy Duration up to 32 Weeks in Patients With Twin Gestations Who Underwent Cerclage Placement [ID: 1378167

Abstract

INTRODUCTION: Historically, cerclages were not recommended in multiple-gestation pregnancies because of uncertain efficacy and concern for harm. However, a meta-analysis of twin pregnancies found cerclage was associated with reduction in preterm birth (PTB) less than 32 weeks with cervical length (CL) of 15 mm or lower. METHODS: We conducted a retrospective analysis of women who underwent cervical cerclage placement at a single tertiary academic center from 2008 to 2020. Data pertaining to maternal demographics, obstetric course, sonographic CL, and cerclage operative technique were abstracted for women with twin gestations. Factors with P value of .2 or lower on univariate analysis of spontaneous PTB (sPTB) less than 32 weeks were considered for incorporation along with history of sPTB into a Cox proportional-hazards model to assess factors associated with pregnancy duration up to 32 weeks. RESULTS: Seventy-five twin gestations were analyzed. On univariate analysis, neuraxial anesthesia during cerclage placement, preoperative cervical dilation, use of Foley catheter for membrane elevation, shorter postoperative CL, and twin B male sex were found to be significantly associated with sPTB less than 32 weeks. Cox proportional-hazards analysis demonstrated that use of Foley catheter for membrane elevation, neuraxial anesthesia, postoperative CL less than 25 mm recorded 24 weeks or earlier, and history of sPTB greater than 16 weeks had significantly higher adjusted hazard ratios. The bias-corrected bootstrapped (1,000 repetitions) AUROC for a logistic regression model with these four covariates predictive of sPTB less than 32 weeks was 0.83 (95% CI 0.69–0.89). CONCLUSION: A survival analysis approach offers valuable clinical insight into predictors of shorter pregnancy duration up to 32 weeks in twin gestations undergoing cervical cerclage placement.