Comparison by Mode of Delivery of Preterm Pregnancy Inductions with Cervical Ripening Balloon: A Retrospective Chart Review ^†

Background: Preterm inductions may be necessary for maternal comorbidities or fetal abnormalities. Previous studies have identified risk factors for undergoing a cesarean delivery (CD). Our study examined the insertion-to-expulsion time (IET) of cervical ripening balloons (CRB) in preterm inductions that achieved vaginal delivery (VD) compared to CD. Methods: This was a retrospective cohort study of preterm inductions with CRB between 2010 and 2021. Primary outcome was IET of CRB. IRB approval was obtained. Results: The study included 82 women. IET for cesarean patients was significantly greater, and required more removal of CRB at the allotted 12 h. Dilation before and after CRB was significantly greater in the vaginal cohort. There was no significant difference in maternal comorbidities, indication for induction or neonatal complications. Conclusions: Maternal comorbidities, induction indication and neonatal complications were similar between cohorts, making trial of induction with CRB in preterm women a reasonable option. Spontaneous expulsion of CRB and greater dilation may be predictors of vaginal delivery.