A Comparison between Single Dose of 50 µµµµµg Oral Misoprostol and 25 µµµµµg Vaginal Misoprostol for Labor Induction
Rita Paisarntantiwong MD, Dip Thai Board of Obstet & Gynecol, MHPE *, Mayuri Getgan MD*
Affiliation : * Department of Obstetrics and Gynecology, Bangkok Metropolitan Administration (BMA) Medical College and Vajira Hospital
Objective : To compare the efficacy and safety of a single dose of 50 µg oral misoprostol with 25 µg vaginal
misoprostol for labor induction.
Materials and Methods : This study was a randomized, double-blind controlled trial conducting in pregnant
women admitted at delivery room, Department of Obstetrics and Gynecology, Bangkok Metropolitan Admin-
istration Medical College and Vajira Hospital between March 2002 and January 2005. All 146 pregnancies
at > 37 weeks’ gestation who had indication for labor induction with unfavorable cervix were randomly
divided into a group of single dose of 50 µg misoprostol orally or 25 µg misoprostol vaginally. Initial and six
hours after misoprostol administration, Bishop scores were evaluated. Requirement of oxytocin augmenta-
tion, complication due to uterine hypertonus, incidence of vaginal delivery, Apgar score at 1 and 5 minutes,
and number of neonate admitted at neonatal intensive care unit (NICU) were recorded.
Results : The baseline characteristics and median initial Bishop scores were comparable in both groups. At 6
hours after misoprostol administration the median cervical changes of women who received oral or vaginal
misoprostol were statistically significant different, 3 and 4, respectively. The median time interval to vaginal
delivery of women who received oral misoprostol was significantly longer than of those who had vaginal drug,
16.9 and 11.8 hours respectively. Comparable neonatal outcomes were found in both groups in terms of
assigned Apgar score at 1 and 5 minutes.
Conclusion : A single dose of 25 µg vaginal misoprostol appears to be more effective than 50 µg oral dose in
improving Bishop scores and decreasing the time to vaginal delivery in women with unfavorable cervix
without severe adverse effects.
Keywords : Labor induction, Cervical ripening, Single dose misoprostol, Oral, Vaginal
