Foley Catheter Versus Vaginal Prostaglandin E2 Gel for Induction of Labor at Term (PROBAAT Trial)

Abstract

Pharmacological methods (e.g., prostaglandins) are the primary means for induction of labor in women with an unfavorable cervix. However, mechanical methods are also used, most commonly a Foley catheter balloon. When used for induction, it has been demonstrated that the Foley catheter and prostaglandins have similar cesarean rates. However, it is unclear whether the rates of fetal distress, postpartum hemorrhage, or other complications differ between the 2 methods. Moreover, there are concerns that the use of the Foley catheter for induction may increase the risk of maternal and neonatal infection. This open-label randomized controlled trial compared the effectiveness and safety of a Foley catheter and vaginal prostaglandin E2 gel for induction of labor in women with an unfavorable cervix in a term pregnancy. The study was conducted in 12 hospitals in the Netherlands between 2009 and 2010. The participants were women with a term pregnancy, singleton gestation, cephalic presentation, intact membranes, an indication for induction, and no previous cesarean delivery. All were randomly assigned to either induction of labor with a Foley catheter (n = 412) or vaginal prostaglandin E2 gel (n = 412). The primary study outcome measure was the cesarean rate. Secondary outcomes included time from intervention to birth and maternal and neonatal morbidity. There was no significant difference in cesarean rates between the 2 groups (23% vs. 20%); the risk ratio was 1.13, with a 95% confidence interval of 0 · 87–1 · 47 (P = 0.38). Findings from a meta-analysis, including the results of this trial, confirmed that use of the Foley catheter for induction does not reduce the cesarean section rate compared with use of prostaglandin E2 gel. Use of the Foley catheter was associated with a lower rate of operative delivery for suspected fetal distress and fewer admissions of newborns to neonatal intensive care units. The only serious maternal adverse events—1 uterine perforation and 1 uterine rupture—occurred in the prostaglandin group. These findings indicate that induction of labor with the Foley catheter in term women with an unfavorable cervix has similar cesarean rates compared with vaginal prostaglandin E2 gel, with fewer side effects.