The induction of labor with balloon catheter after a previous cesarean section, a retrospective cohort study

Introduction: The induction of labor on a scarred uterus is a challenge for obstetricians and requires both effective and safe methods.

Material and methods: In this retrospective study we included 190 term pregnancies: 113 women where the induction of labor was performed with a balloon catheter and 77 women where the labor was induced with oxytocin. We excluded all pregnancies with lethal congenital anomalies. As a primary outcome we compared the rate of vaginal deliveries between the two groups. Further we compared in each group the rate of vaginal, respectively CS deliveries between women with and without a prior vaginal delivery. Secondary outcomes were the rate of maternal complications as well as the fetal status defined through specific parameters (APGAR score after 5 minutes, arterial pH values, neonatal admission after birth).

Results: The vaginal delivery rate reached 38.93% (n = 44) in the catheter group and 63.63% (n = 49) in the oxytocin group. In the catheter group 50% of the women that had a prior vaginal delivery gave birth naturally. In the oxytocin group 86.36% of the women with prior vaginal delivery had a vaginal delivery in this pregnancy. 27.43% of the newborns in the catheter group needed a neonatal admission after birth vs. 14.28% in the oxytocin group.

Conclusions: The induction of labor by administrating an oxytocin infusion is an effective and safe method for the scarred uterus and a good alternative to the primary CS. The induction with balloon catheter is also a safe method for the less riper cervix, the rate of vaginal delivery is nevertheless lower. A prior vaginal delivery had no influence on the outcome of the current pregnancy when the birth was induced with a catheter, but increased the chances for a new vaginal delivery in the oxytocin group. The neonatal admission after birth was significantly lower when the labor was induced with oxytocin. The other parameters (APGAR score, arterial pH values) were comparable in the two groups.