Induction of labor in high-risk nulliparous women with unfavorable cervix.

Background: Inducing labor by ensuring a good maternal-fetal outcome is a challenge. The aim of the study was to evaluate the success rate, safeness, and time to delivery after the induction of labor (IOL), with the alternately first use of dinoprostone or Foley balloon, in high-risk pregnancy nulliparous women with unfavorable Bishop Score (BS).

Methods: This is a retrospective study of high-risk nulliparous women who underwent the IOL, either with dinoprostone or the Foley balloon method. In the former case, if the labor has not started after dinoprostone removal, oxytocin infusion started. In Foley group, the BS was re-evaluated after Foley removal, and IOL continued with the use of dinoprostone (if BS<6) or oxytocin (if BS>6). Here, too, if no labor occurred after dinoprostone removal, Oxytocin was administered. Delivery mode, fetal and maternal complications were recorded. The time to delivery was tracked.

Results: A total of 261 women were enrolled in the study. The CS rate was similar between groups (37.56% vs. 35.93%; P=0.81). Time to delivery was statistically lower in dinoprostone group (26.82h), as opposed to Foley (47.4h) (P<0.0001). Body Mass Index (BMI) of women who underwent Cesarean section (CS) was significantly higher than women who gave birth by vaginal delivery (VD), 26.80 vs. 27.40, P=0.012.

Conclusions: IOL in high-risk pregnancy nulliparous women resulted in equal rate of CS between the two groups. Dinoprostone first use resulted in a shorter time to delivery, with no maternal-fetal side effects. There is then no need to prolong IOL and raise maternal stress, as this will not yield better outcomes.