Sublingual Misoprostol for Induction of Labor

Several methods for induction of labour are available. However, the most effective and with less frequency of adverse effects is still unknown. Vaginal misoprostol has been used frequently to induce labour but other routes of administrations have been proposed, such as oral and sublingual. The purpose of this study is to compare effectiveness and safety of sublingual misoprostol 12,5 mcg with vaginal misoprostol 25 mcg administration for induction of labour with an alive and term fetus. A randomized controlled double-blind trial will be carried in two hospitals: Instituto de Medicina Integral Prof. Fernando Figueira and Universidade Federal do Ceará and Instituto de Saúde Elpídio de Almeida, from July 2014 to November 2016. A total of 150 patients must be enrolled. Inclusion criteria are: a) indication for labour induction; b) term pregnancy with alive fetus; Bishop score less than six. Exclusion criteria are: a) previous uterine scar; b) nonvertex presentation; c) non-reassuring fetal status; d) fetal anomalies; e) fetal growth restriction; f) genital bleeding; g) tumors, malformations and/or ulcers of vulva, perineum or vagina. They will be randomized to receive a sublingual misoprostol 12,5 mcg with vaginal placebo tablet or sublingual placebo with vaginal misoprostol 25 mcg tablet. Vaginal tablets will have 25mcg of misoprostol or placebo. Sublingual tablet will have 12,5mcg or placebo. Vaginal misoprostol or placebo tablets will be administered for each six hours until the maximum dose of 200mcg or eight tablets. Primary outcome will be the frequency of tachysystole. Secondary outcomes will be vaginal delivery within 24 hours, hyperstimulation syndrome, cesarean section, severe neonatal morbidity or perinatal death, serious maternal morbidity or maternal death, need of oxytocin for augmentation of labour, number of misoprostol doses needed to bring on labour, interval from first dose to labour and first dose to delivery, failed induction, uterine rupture, need of labour analgesia, instrumental delivery, side effects, maternal death, meconium, non-reassuring fetal heart rate, Apgar scores less than seven at 1st and 5th minutes, admission at neonatal intensive care unit, neonatal encephalopaty, perinatal death and women not satisfied.

Inclusion criteria

• Indication for labour induction
• Term pregnancy with alive fetus
• Bishop score less than six

Exclusion criteria

• Previous uterine scar
• Nonvertex presentation
• Non-reassuring fetal status
• Fetal anomalies
• Fetal growth restriction
• Genital bleeding
• Tumors, malformations and/or ulcers of vulva, perineum or vagina