ATLANTA – Women whose labor was induced by a combination medication and cervical Foley catheter progressed to vaginal delivery almost twice as fast as those induced by a single method.
The combination of misoprostol and a cervical Foley was the most effective, with a mean time to vaginal delivery of 11 hours, compared with 16 hours for the drug and the catheter alone, Dr. Lisa Levine reported at the annual Pregnancy Meeting sponsored by the Society for Maternal-Fetal Medicine.
When only vaginal deliveries were considered, the combination was 92% faster than misoprostol alone and 87% faster than Foley alone, said Dr. Levine of the University of Pennsylvania, Philadelphia.
The findings are from a four-armed randomized trial – and the only head-to-head comparison of combination and single-method induction. The findings could be practice-changing, she said.
Dr. Lisa Levine
“More than 20% of pregnant women undergo an induction each year – that’s almost 1 million women,” she said. “If combination methods were used for all these women, there would be more than 3.5 million fewer hours of labor. This would have a large impact on healthcare utilization. If we could find a way to shorten the length of labor without increasing the cesarean delivery rate or neonatal complications, this would have an obvious clinical impact.”
The Foley or Misoprostol for the Management of Induction (FOR MOMI) trial randomized 491 women to four treatment arms: misoprostol alone, Foley cervical catheter alone, misoprostol plus Foley, and oxytocin plus Foley. The primary outcome was time to delivery, regardless of mode. Secondary outcomes were time to vaginal delivery; delivery within 24 hours; time to active labor; maternal and neonatal length of stay; and chorioamnionitis.
There were also composite morbidity outcomes for mother and newborn.
Women in the study were a mean of 27 years old. Most (about 72%) were nulliparous. The mean gestational age at induction was 39 weeks. The mean Bishop score at induction was 3; the mean dilation, 1 cm.
In the primary outcome of time to any delivery, both combination methods led to shorter labor times in both vaginal and cesarean deliveries. Time to delivery was 17 hours in both the misoprostol- and Foley-only groups. It was 13 hours in the misoprostol/Foley combination group, and 14.5 hours in the oxytocin/Foley combination group. Both combination methods led to significantly quicker deliveries in both nulliparous and multiparous women.
The combination methods were also significantly more efficient in the group of only vaginal deliveries. The mean time to vaginal delivery was 11 hours for both combination groups, and 16 hours for both misoprostol- and Foley-only inductions. Again, these differences were seen in both nulliparous and multiparous women.
More women in the combination groups delivered within 24 hours of induction (88% in the misoprostol/Foley group; 84% in the oxytocin/Foley group).
In an analysis that removed all the cesarean deliveries and controlled for other factors, only the combination of misoprostol/Foley retained its significant effect on time to vaginal delivery.
There were no significant between-group differences in the rates of cesarean delivery. The composite measure of maternal morbidity was similar between all the groups. There were no differences in the individual rates of arrest lacerations, endometritis, blood transfusion, infection, readmission, wound dehiscence, or length of stay.
There was no significant difference in any of the neonatal outcomes measures, including Apgar, admission to the neonatal intensive care unit, as well as length of stay, sepsis, or respiratory distress syndrome.
The University of Pennsylvania sponsored the study. Dr. Levine reported having no financial disclosures.