Labor Induction Outcomes with Outpatient Misoprostol for Cervical Ripening among Low-Risk Women

Objective In 2012, two Kaiser Permanente Northern California (KPNC) hospitals began offering outpatient cervical ripening with oral misoprostol under a study protocol. We evaluated inpatient time from admission to delivery and adverse maternal and neonatal outcomes associated with outpatient use of misoprostol for cervical ripening among low-risk women with term pregnancies. Study Design We conducted a retrospective cohort study comparing three groups: women who received misoprostol (1) outpatient, under a study protocol; (2) inpatient, at the study sites; and (3) inpatient, at all KPNC hospitals. Data were obtained from between 2012 and 2017. The primary outcome was time from inpatient admission to delivery. Secondarily, we evaluated maternal and neonatal outcomes, including the duration and maximum rate of oxytocin administered, rate of cesarean delivery, incidence of chorioamnionitis and blood transfusion, Apgar scores, and neonatal intensive care unit admissions. Demographic and clinical characteristics and outcomes of the outpatient group were compared with both inpatient misoprostol groups using the appropriate statistical test. Variables included in the regression analysis were either statistically significant in the bivariate analyses or have been reported in the literature to be potential confounders: maternal age at admission, race/ethnicity, body mass index, cervical dilation at initial misoprostol, and parity. Results We analyzed data from 10,253 patients: (1) 345 outpatients, under a study protocol; (2) 1,374 inpatients, at the study sites; and (3) 9,908 inpatients, at all the Kaiser hospitals. Women in the outpatient group were more likely to be white than both inpatient groups (63.3 vs. 56.3% at study sites and 47.1% in all hospitals, p = 0.002 and Conclusion Outpatient use of misoprostol for cervical ripening under the study protocol was associated with reduced inpatient time from admission to delivery compared with inpatient misoprostol. Although there was a higher rate of chorioamnionitis among outpatients under the study protocol compared with inpatients at all hospitals, there was no difference when compared with inpatients at the study sites. There was no difference in rates of cesarean delivery or maternal or neonatal complications with outpatient misoprostol. Key Points