Objective: To assess whether outpatient cervical ripening with a transcervical Foley catheter in parous women undergoing elective induction of labor shortens the total duration of time from admission to the labor ward until delivery.
Methods: We performed an open-label randomized controlled trial at a single academic center in parous women at 39 weeks of gestation or greater with a cervix 3 cm or less dilated, or, if 2-3 cm dilated, less than 80% effaced and reassuring fetal heart rate monitoring (defined as moderate variability with a normal baseline and absence of decelerations). Exclusions were obstetric and neonatal conditions deemed unsuitable for outpatient cervical ripening, contraindications to vaginal delivery, or conditions that required immediate hospitalization. Women were randomized in the ambulatory setting to either an outpatient transcervical catheter (with immediate placement) or inpatient transcervical catheter placement and concomitant oxytocin infusion on the labor ward. Women in the outpatient group were instructed to return to the hospital the next day or sooner if labor occurred. Induction of labor was managed per institutional protocol, and once participants were admitted, oxytocin was initiated. The primary outcome was the duration of time from labor ward admission until delivery. Based on a prior study in our institution, a total of 128 women were needed for 80% power to detect a 12-hour difference in total duration spent from labor ward admission until delivery with a two-sided α of 0.05.
Results: Of 743 women screened, 129 provided consent and were randomized from May 2016 to October 2017. Baseline characteristics were balanced between groups. Outpatient cervical ripening did not significantly shorten the time from labor ward admission until delivery (12.4±7.4 vs 13.5±7.0 hours, P=.38).
Conclusion: Outpatient cervical ripening in parous women does not shorten the time from labor ward admission until delivery if oxytocin is initiated simultaneously with inpatient transcervical catheter placement.
Clinical trial registration: ClinicalTrials.gov, NCT02756689.