309: Foley balloon insertion by blind placement versus direct visualization: A randomized controlled trial (FRIENDLY)

Abstract

To test the hypothesis that digital placement of a balloon catheter is not inferior to the speculum method in terms of rate of maternal infection. Pregnant women >37 weeks undergoing induction of labor with unfavorable cervix (< 3 cm and < 60% effaced) were randomly assigned to balloon catheter placed either digitally (DP) or using a sterile speculum (SS). The cervix was cleaned with Betadine before insertion in the SS group. The balloon was inflated with 60 mL of sterile saline and left up to 12 hours. If the cervix remained unfavorable, one more round of balloon ripening was performed. All other management, including the use of oxytocin, was left to the discretion of the clinical providers. The primary outcome was a composite of maternal infection, defined by occurrence of fever, chorioamnionitis, or endometritis. Secondary outcomes are listed in Table. Patients completed a satisfaction survey. On the basis of a non-inferiority margin of 10% and an expected primary outcome frequency of 10%, a sample size of 372 women was needed (90% power to confirm non-inferiority with 90% protocol adherence). 372 women were randomized (185 digital, 187 speculum). Composite maternal infection rate was higher in the digital arm (15.7% vs. 12.8%), with an absolute difference with respect to the speculum arm of 2.8% (95% CI -4.3% to 9.9%), indicating non-inferiority for the pre-specified margin (Figure). Secondary outcomes were not different between groups, except for higher need for a second balloon catheter in the speculum arm (Table). Maternal and neonatal adverse events and responses on the satisfaction survey were not different between groups. Digital placement of a balloon catheter for pre-induction cervical ripening is non-inferior to the sterile-speculum method in terms of maternal infection. Women in the sterile speculum group required a second round of the mechanical dilator more frequently. The blind digital approach is a reasonable option for balloon placement for cervical ripening.View Large Image Figure ViewerDownload Hi-res image Download (PPT)