The studies in this review are limited by sample size which are often divided into multiple comparison groups. Most comparisons showed no significant differences, with wide confidence intervals. Although extra-amniotic prostaglandins may be as effective as other modalities in initiating labour, there is little conclusive information from this review to guide clinical practice. An adequately powered randomised controlled trial would be useful to determine if the use of extra-amniotic prostaglandins would lower the rate of caesarean section.
Labor induction with vaginal misoprostol and extra-amniotic prostaglandin F2alpha gel.
To compare the effectiveness of vaginally administered misoprostol with extra-amniotic prostaglandin F2alpha (PGF2alpha) gel for induction of labor.
                A randomized controlled trial, with women allocated to receive either misoprostol 50 microg intra-vaginally or extra-amniotic PGF2alpha gel 5 mg, was conducted in Harare Maternity Hospital. A total of 152 women were admitted for induction of labor with a term singleton, pregnancy and cephalic presentation were recruited. The main outcome was duration of induction.
                There were no differences in the characteristics of women in the two groups at recruitment. In the misoprostol group there was a significantly reduced need for augmentation of labor with oxytocin (OR=0.36; 95% C.I. 0.17-0.73) and delivery by cesarean section for failure to progress (OR=0.11; 95% C.I. 0.00-0.88). The risk for duration of induction to vaginal delivery exceeding 12, 18 or 24 h was reduced by 18%, 38% and 68%, respectively, but only the risk for duration >24 h was significantly reduced (OR=0.32; 95%C.I. 0.11-0.91). The mean duration of induction was shorter in the misoprostol group, 15.2 vs. 23.6 h (P=0.02). There were no differences in fetal outcome.
                Misoprostol 50 microg was associated with less use of oxytocin in labor, a shorter induction to delivery interval and fewer cesarean sections for failure to progress when compared with extra-amniotic PGF2alpha gel.