A randomized comparison of oral mifepristone to intravenous oxytocin for labor induction in women with prelabor rupture of membranes beyond 36 weeks' gestation.
OBJECTIVE
This study was undertaken to compare the use of oral mifepristone with intravenous oxytocin for labor induction in women with prelabor rupture of membranes (PROM) at 36 weeks' or greater gestational age.


METHODS
Sixty-five women with spontaneous PROM were randomly assigned to receive orally administered mifepristone or oxytocin infusion. Two hundred milligrams of mifepristone was administered, and subjects were observed for 18 hours, or intravenous oxytocin was administered.


RESULTS
Thirty-three women received mifepristone and 32 received oxytocin. The average interval from start of induction to delivery was 1194.1 +/- 568.7 minutes for mifepristone-treated subjects and 770.8 +/- 519.9 minutes for oxytocin-treated subjects ( P = .001, log-transformed data). Of 33 mifepristone-treated subjects and 32 oxytocin-treated subjects, 25 (78.1%) and 17 (51.5%), respectively, achieved successful induction (defined as vaginal delivery within 24 hours) (relative risk [RR] 0.66, 95% CI 0.45-0.96, P = .01). There was more fetal distress in the mifepristone-treated group (9 vs 2, RR 4.36, 95% CI 1.02-18.66, P = .02), and a trend toward more cesarean births (7 vs 3, RR 2.26, 95% CI 0.64-7.99, P = .19). Eleven infants of mifepristone-treated women (33.3%) and 3 infants of oxytocin-treated women (9.4%) were admitted to the neonatal intensive care unit (RR 3.56, 95% CI 1.09-11.58, P = .02).


CONCLUSIONS
Oral mifepristone administration 18 hours before oxytocin infusion did not improve labor stimulation in women with PROM near term, and was associated with more adverse fetal outcomes.
Wing
Deborah A
DA
Women's and Children's Hospital, Department of Obstetrics-Gynecology, Division of Maternal-Fetal Medicine, University of Southern California, Keck School of Medicine, Los Angeles, Calif, USA.
Guberman
Cristiane
C
Fassett
Michael
M
D000284:Administration, Oral; D000328:Adult; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000628:therapy*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007262:Infusions, Intravenous; D007363:Intensive Care Units, Neonatal; D007751:Labor, Induced / Q000379:methods*; D015735:Mifepristone / Q000008:administration & dosage / Q000627:therapeutic use*; D010121:Oxytocin / Q000008:administration & dosage / Q000627:therapeutic use*; D011247:Pregnancy
D015735:Mifepristone; D010121:Oxytocin