(1035) Vaginal compared with oral misoprostol induction for individuals with morbid obesity

Friday, January 31, 2025

4:00 PM – 6:00 PM

Submitting Author and Presenting Author(s)

Gayathri D. Vadlamudi, MD (she/her/hers)

Fellow
UT Southwestern Medical Center
Ypsilanti, MI, United States

Coauthor(s)

DM

Donald D. McIntire, PhD

University of Texas Southwestern Medical Center
Dallas, Texas, United States
Emily H. Adhikari, MD

Assistant Professor
University of Texas Southwestern Medical Center
Dallas, Texas, United States

Objective: To characterize labor progress in term individuals with morbid obesity undergoing induction using vaginal compared with oral misoprostol

Study Design: We conducted a secondary analysis of a cluster randomized controlled trial comparing oral or vaginal misoprostol regimens for term labor induction among individuals with intact membranes and cervical dilation ≤ 2cm. Pregnant persons with BMI ≥ 40kg/m2 at delivery were included. Weekly randomization was assigned to either oral (100 µg every 4 hours for up to two doses) or vaginal (25 µg every 3 hours for up to five doses) misoprostol, followed by a standardized oxytocin protocol. We recorded cervical exams at misoprostol administrations, oxytocin initiation, and prior to delivery. We compared labor progress and duration, need for oxytocin, and delivery and neonatal outcomes using generalized estimating equations to account for clustering. Outcomes were stratified by parity. Labor curves were constructed using a mixed effects repeated measures model.

Results: Of 491 patients, 264(53.8%) received vaginal and 227(46.2%) oral misoprostol. There were no significant demographic differences. Route of administration was not associated with a difference in time (hours) to delivery (22.9±0.74 vaginal vs 22.3±0.78 oral). Among 165(66.2%) vaginal and 137(62.8%) oral misoprostol recipients who reached the second stage of labor, length of first stage did not differ (20.6±0.81h vs 20.5±0.89h). Need for oxytocin was lower with vaginal misoprostol (188(71.2%) vs 194(85.5%). There were no significant differences in vaginal delivery or other maternal and neonatal outcomes including umbilical cord pH < 7.0 and neonatal intubation. Associations between route of misoprostol and outcomes were similar after stratification by parity. Rate of cervical dilation did not differ by route of administration.

Conclusion: In patients with morbid obesity undergoing term induction, route of misoprostol does not impact time to delivery or vaginal delivery rates.