Efficiency of the Foley catheter versus the double balloon catheter during the induction of second trimester pregnancy terminations: a randomized controlled trial

To compare induction-to-delivery intervals of Foley catheters and double balloon catheters in second trimester pregnancy terminations.

This randomized parallel study was conducted on women who underwent second trimester terminations between December 2016 and December 2017. Pregnant women in the second trimester with a Bishop score < 6 were included in the study. Participants were randomized into two groups, the first being the Foley catheter group and the second being the double balloon catheter group. The time frames from insertion of catheters to the delivery were recorded in each group. A multiple regression analysis was carried out to examine the contribution of factors to the induction-to-delivery interval. A survival analysis was conducted to compare the Foley method and the double balloon method.

A total of 91 pregnant women were included in the final analysis. The induction-to-delivery interval was shorter in the Foley catheter group than in the double balloon catheter group (38 h 54 min ± 21 h 6 min versus 58 h 17 min ± 25 h 56 min). We also found that women with intrauterine fetal death (IUFD) had a shorter time to delivery compared to women with live fetuses (39 h 12 min ± 18 h 46 min vs 51 h 30 min ± 26 h 42 min, p = 0.04). Women with a history of vaginal delivery also had a shorter induction-to-delivery time compared to women who never delivered vaginally before (38 h 12 min ± 17 h 42 min vs 53 h 54 min ± 27 h 18 min, p = 0.004). In the multiple regression analysis, the most significant contributor to the induction-to-delivery time was the method used for induction of labor and followed by other factors including the viability of the fetus (live/IUFD), history of vaginal delivery and PPROM. The survival analysis showed that the induction-to-delivery interval was significantly shorter in the Foley catheter group than in the double balloon catheter group (HR 2.51, 95% CI 1.57–4.00, p = 0.001).

During the termination of second trimester pregnancies time from induction of labor to delivery is shorter with the Foley catheter compared to double balloon catheter.