Induction of labour in mid-trimester pregnancy using double-balloon catheter placement within 12 hours versus within 12-24 hours

Abstract Background This study aims to evaluate the efficacy and safety of the induction of labour in mid-trimester pregnancy using double-balloon catheter (DBC) within 12 hours versus within 12–24 hours. Methods In this retrospective study, a total of 58 pregnant women with gestation age of 14 + 0 weeks to 27 + 6 weeks were enrolled as research objects, and they underwent intended termination of pregnancy at our birth center from January 1, 2017, to June 31, 2019. Based on the duration time of DBC, the cases were divided into two groups (DBC group within 12 hours and DBC group within 12–24 hours). Results All of the 58 cases were successful vaginal delivery and no one chose cesarean section. The success rate of induction (successful abortion of fetus and placenta without the implementation of dilatation and evacuation) was higher in the DBC group within 12–24 hours (96.3%, 29/31) than that in DBC group within 12 hours (71.0%, 18/27) (p < 0.05). At the same time, the time from DBC removal to delivery in 12–24 hours DBC group was significantly shorter than that in DBC group within 12 hours (3.0 h versus 17.8 h) (p < 0.05), the degree of cervical dilation after DBC removal in DBC group within 12–24 hours was larger than that in DBC group within 12 hours (p < 0.05). Conclusion In the clinic, the placement time of DBC is generally lasting for about 12 hours. However, considering the cervical condition is immature in the mid-trimester, properly extending the placement time of DBC to 24 hours will benefit for cervical ripening and lead to reduce chance of dilatation and evacuation.