To compare the effectiveness and safety of oral misoprostol to the vaginal dinoprostone insert for the induction of labor of nulliparous women at term.
Records of women admitted to Lucile Packard Children's Hospital from January 2008 to December 2010 for labor induction with an unfavorable cervix were reviewed. Patients receiving oral misoprostol as the primary induction agent were compared with those receiving vaginal dinoprostone. Multiparous patients and those with multiple or preterm gestations, membrane rupture, or use of other primary induction agents were excluded. The primary outcome was defined as time interval from administration of the primary induction agent to vaginal delivery. Secondary outcomes included vaginal delivery in less than 24 hours, use of secondary ripening or augmentation agents, and maternal and fetal outcomes.
1016 patient records were reviewed. 680 met inclusion criteria: 483 (71%) received vaginal dinoprostone and 197 (29%) received oral misoprostol. Patients receiving oral misoprostol were more likely to be Hispanic (40% vs. 35%, p=0.04), and to have greater cervical dilation on admission (mean = 0.63 cm vs. 0.98 cm, p<0.001). Time interval from induction to vaginal delivery was shorter with oral misoprostol (27.2 vs. 21.9 hours, p< 0.001). This difference remained significant when controlling for cervical dilation, regional anesthesia, and birthweight. After risk adjustment, the odds of vaginal delivery in less than 24 hours was two times greater with oral misoprostol (OR 2.26, CI=1.42-3.58). Patients receiving oral misoprostol were more likely to deliver vaginally (71% vs. 63%, p=0.04); however no difference was seen after adjusting for possible confounders. There were no differences in any of the secondary maternal or fetal outcomes.
In nulliparous women, oral misoprostol as the primary cervical ripening agent resulted in a shorter interval to vaginal delivery.
© 2013 Mosby, Inc. Published by Elsevier Inc. All rights reserved.