Background
Premature rupture of membranes (PROM) occurs in 8% of pregnancies. In the absence
of spontaneous labor, induction of labor is considered an appropriate strategy for
term pregnant women with PROM. There are several approaches for pre-induction cervical
ripening, including mechanical methods, such as Foley catheterization, and non-mechanical
methods, such as oral misoprostol.
Objective
The purpose of this study was to evaluate and compare the effects of oral misoprostol
and Foley catheterization in pregnant women with PROM ≥34w who underwent induction
of labor.
Study design
A randomized clinical trial was performed. Inclusion criteria were nullipar and multipar
pregnant women ≥ 34 weeks of gestational age (GA), singleton pregnancies with cephalic
presentation with confirmed amniotic fluid leakage for more than 60 minutes. A total
of 104 participants were randomly allocated into two groups, one receiving sublingual
misoprostol (miso) and the other receiving transcervical Foley catheter (FC) 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 (ABG) analysis
of the umbilical cord.
Results
The mean time from induction to delivery (11.6 ± 1.98 for FC vs. 10.16 ± 2.35 hours
for miso, P=0.007) and the median duration of cervical ripening (4.5 (0.0-6.0) for
FC vs. 4.0 (1.5-6.0) hours for miso, P=0.04) was longer in the FC group. There was
no statistically significant difference in the cesarean delivery rate between the
two groups (29.6% for FC vs 38.5% for miso, P=0.2). There were no cases of chorioamnionitis
or asphyxia in the two groups. There was no significant difference between the two
groups in terms of umbilical cord pH, and the first and fifth minute Apgar scores
(P=0.1, P=0.4, and P=0.1); nevertheless, these values were higher in the FC group.
There were no statistically significant differences among additional secondary outcomes.
Conclusion
Cervical ripening in PROM cases with FC is associated with longer duration of ripening
and time from induction to delivery compared to ripening with misoprostol. The cesarean
delivery rate and the maternal and neonatal infection rates were not different between
these methods.