Misoprostol for induction of labour at term: a more effective agent than dinoprostone vaginal gel

Objective To compare the efficacy of vaginal misoprostol and dinoprostone v aginal gel for induction of labour at term. Design A single-blind randomised comparative trial. Setting Induction and labour wards of a UK teaching hospital. Participants Two hundred and eleven pregnant women at term in whom inductio n of labour was indicated, and with no contra-indication to the use of pros taglandins for the induction of labour. Intervention The women were randomly assigned to receive vaginal administra tion of either misoprostol 50 mu g four hourly (to a maximum of four doses) or dinoprostone gel 1 mg six hourly (to a maximum of three doses). Main outcome measures Time from induction to delivery, oxytocin requirement in labour, analgesic requirement, mode of delivery, neonatal outcome. Results The misoprostol. group had a highly significant reduction in median induction-delivery interval compared with the dinoprostone group (14.4 hou rs vs 22.9 hours; P < 0.00001). In addition, more women delivered after onl y one dose (77% vs 49%; P < 0.0001, OR 3.51, 95% CI 1.94-6.35), and within 12 and 24 hours. There was a reduced need for oxytocin augmentation in labo ur (21% vs 47%; P < 0.0001, OR 0.30, 95% CI 0.16-0.54). There was no differ ence in analgesia requirement in labour, or in mode of delivery. There were no adverse neonatal outcomes associated with the use of misoprostol. Women in the misoprostol group experienced more pain in the interval between ind uction and being given analgesia in labour, but this did not reach statisti cal significance. Conclusions Misoprostol 50 mu g vaginally is a more effective induction age nt than 1 mg dinoprostone vaginal gel, with no apparent adverse effects on mode of delivery, or on the fetus. The higher pain scores in the misoprosto l group must be balanced against the reduction in time spent having labour induced, and the reduction in need for intravenous oxytocin augmentation. F urther randomised studies must continue to exclude the possibility of rare adverse side effects.