Oral misoprostol, low dose vaginal misoprostol, and vaginal dinoprostone for labor induction: Randomized controlled trial

Abstract

Objective To compare effectiveness and safety of oral misoprostol (50 μg every four hours as needed), low dose vaginal misoprostol (25 to 50 μg every six hours as needed), and our established dinoprostone vaginal gel (one to two mg every six hours as needed) induction. Materials and methods Consenting women with a live term single cephalic fetus for indicated labor induction were randomized (3N = 511). Prior uterine surgery or non-reassuring fetal surveillance were exclusions. Concealed computer generated randomization was stratified and blocked. Newborns were assessed by a team unaware of group assignment. The primary outcome was time from induction at randomization to vaginal birth for initial parametric analysis. Sample size was based on mean difference of 240 minutes with α 2 = 0.05 and power 95%. Nonparametric analysis was also pre-specified ranking cesareans as longest vaginal births. Results Enrollment was from April 1999 to December 2000. Demographics were similar across groups. Analysis was by intent to treat, with no loss to follow up. Mean time (±SD) to vaginal birth was 1356 (±1033) minutes for oral misoprostol, 1530 (±3249) minutes for vaginal misoprostol, and 1208 (±613) minutes for vaginal dinoprostone (P = 0.46, ANOVA). Median times to vaginal birth were 1571, 1339, and 1451 minutes respectively (P = 0.46, Kruskal-Wallis). Vaginal births occurred within 24 hours in 44.9, 53.5 and 47.7% respectively (P = 0.27, χ 2). There were no significant differences in Kaplan Meier survival analyses, cesareans, adverse effects, or maternal satisfaction. The newborn who met birth asphyxia criteria received vaginal misoprostol, as did. all three other newborns with cord artery pH<7.0 (P = 0.04, Fisher Exact).

Vaginal dinoprostone and misoprostol are equally safe in labour induction at term whereas dinoprostone is less efficacious for cervical ripening and shortening the time of labour

“…On the other hand, in the studies by Yehia et al [20], no statistical differences were observed in the occurrence of uterine hyperstimulation in the groups of women undergoing induction with misoprostol and dinoprostone, which may be due to differences in the form and dose of drugs used: titrated oral misoprostol (20 mcg every 2 hours) and vaginal dinoprostone (3 mg). Other studies compared oral misoprostol (50mcg every 4 hours), vaginal misoprostol (25-50mcg every 6 hours) with vaginal gel dinoprostone [23] or vaginal insert dinoprostone (10 mg) [9]. In all the studied groups, the authors did not find statistically significant differences in the occurrence of tachysystole and uterine hyperstimulation.…”

“…A randomized clinical trial is currently in progress regarding efficacy and safety of administering oral misoprostol by titration compared to vaginal misoprostol and dinoprostone for cervical ripening and induction of labor [24]. Most studies reports do not show any increased risk of side effects of misoprostol compared to dinoprostone, as well as worse birth condition of the newborns, longer stay on NICU admission and higher neonatal mortality after induction of labor with misoprostol or dinoprostone [20,22,23,25]. In randomized studies of PLOS ONE -the median birth status of newborns on the Apgar scale at the first and fifth minutes of life did not differ significantly in the groups of mothers induced with prostaglandin analogues: oral or vaginal misoprostol and vaginal dinoprostone [23].…”

“…Most studies reports do not show any increased risk of side effects of misoprostol compared to dinoprostone, as well as worse birth condition of the newborns, longer stay on NICU admission and higher neonatal mortality after induction of labor with misoprostol or dinoprostone [20,22,23,25]. In randomized studies of PLOS ONE -the median birth status of newborns on the Apgar scale at the first and fifth minutes of life did not differ significantly in the groups of mothers induced with prostaglandin analogues: oral or vaginal misoprostol and vaginal dinoprostone [23]. The use of exogenous prostaglandins does not affect the birth condition of newborns, regardless of the exposure time and the time of prostaglandin removal [25].…”

Comparative study of 25 mg oral and 25 mg vaginal misoprostol administration for induction of labour at term

“…A study by Young et al found no significance in the parity in the two groups and for the time and the outcome of delivery. 18 Among the patients who received the induction orally, 24% of them required 2 doses followed by 22% who needed 4 doses. Among the patients with vaginal induction, 40% needed only 2 doses.…”

Efficacy and Safety of Vaginal Misoprostol for Cervical Ripening and Labour Induction in Late Pregnancy

“…Established indications for induction include post-term pregnancy, pre-labor membrane rupture (PROM), and maternal hypertension. 1 The use of misoprostol results in a shorter induction to delivery time, a reduction in rate of caesarean section and without any adverse effect on the mother and the neonatal outcomes. It is rapidly absorbed and is more effective than oxytocin or dinoproston for induction of labour.…”