Evaluation of mechanical and nonmechanical methods of cervix ripening in women with pre-labor rupture of membranes: a randomized controlled trial

Abstract

Background: Pre-labor rupture of membranes occurs in 8% of pregnancies. In the absence of spontaneous labor, induction of labor is considered an appropriate strategy for term pregnant women with pre-labor rupture of membranes. There are several approaches for preinduction cervical ripening, including mechanical methods, such as Foley catheterization, and nonmechanical methods, such as oral misoprostol.

Objective: This study aimed to evaluate and compare the effects of oral misoprostol and Foley catheterization in pregnant women with pre-labor rupture of membranes at ≥34 weeks of gestation who underwent induction of labor.

Study design: A randomized clinical trial was conducted. The inclusion criteria included nulliparous and multiparous pregnant women at ≥34 weeks of gestation with singleton pregnancies, cephalic presentation, and confirmed amniotic fluid leakage for more than 60 minutes. A total of 104 participants were randomly allocated into 2 groups, one receiving sublingual misoprostol and the other receiving transcervical Foley catheter for cervical ripening. The primary outcome was time from intervention to delivery, and the secondary outcomes included delivery method, maternal and neonatal results (chorioamnionitis, Apgar score, neonatal sepsis, and asphyxia), and arterial blood gas analysis of the umbilical cord.

Results: The mean time from induction of labor to delivery (11.6±1.98 hours for Foley catheter vs 10.16±2.35 hours for misoprostol; P=.007) and the median duration of cervical ripening (4.5 hours [interquartile range, 0.0-6.0] for Foley catheter vs 4.0 hours [interquartile range, 1.5-6.0] for misoprostol; P=.04) were longer in the Foley catheter group than in the misoprostol group. There was no statistically significant difference in the cesarean delivery rate between the 2 groups (29.6% for Foley catheter vs 38.5% for misoprostol; P=.2). There was no case of chorioamnionitis or asphyxia in the 2 groups. There was no significant difference between the 2 groups in terms of umbilical cord pH and the 1- and 5-minute Apgar scores (P=.1, P=.4, and P=.1); nevertheless, these values were higher in the Foley catheter group. There was no statistically significant difference among additional secondary outcomes.

Conclusion: In pre-labor rupture of membranes cases, cervical ripening with a Foley catheter was associated with a longer duration of ripening and time from induction to delivery than cervical ripening with misoprostol. The cesarean delivery rate and the maternal and neonatal infection rates were not different between these methods.

Keywords: Foley catheter; cervical ripening; chorioamnionitis; induction of labor; misoprostol; neonatal sepsis; pre-labor rupture of membranes.