The efficacy of misoprostol vaginal insert compared with oral misoprostol in the induction of labor of nulliparous women: A randomized national multicenter trial

Abstract

Introduction Our objective was to compare the efficacy of a 200‐μg misoprostol vaginal insert vs oral misoprostol regarding the cesarean section rate and the time interval to vaginal delivery in nulliparous women with unfavorable cervix. Material and methods In this prospective multicenter trial, 283 nulliparous women at term with Bishop score <6 were randomized to induction of labor with either a misoprostol vaginal insert (n = 140) or oral misoprostol (n = 143). In the oral misoprostol group, a 50‐μg dose of oral misoprostol was administered every 4 hours up to three times during the first day; during the second day, the dose was increased to 100‐μg every 4 hours up to three times during the first day, if necessary. Primary outcome was the cesarean section rate. Secondary outcomes were the time from induction of labor to vaginal delivery, the rate of other induction methods needed, labor augmentation with oxytocin and/or amniotomy, use of tocolytics and adverse neonatal and maternal events. Results In the misoprostol vaginal insert group, median time to vaginal delivery was shorter (24.5 hours vs 44.2 hours, P < 0.001), whereas no difference was found in the cesarean section rate (33.8% vs 29.6%, odds ratio [OR] 1.21, 95% confidence interval [CI] 0.66‐1.91, P = 0.67). Other induction methods and labor augmentation with oxytocin and/or amniotomy were less frequent in the misoprostol vaginal insert group (OR 0.32, 95% CI 0.18‐0.59 and OR 0.56, 95% CI 0.32‐0.99, respectively). Need for tocolysis and meconium‐stained amniotic fluid were more common in the misoprostol vaginal insert group (OR 3.63, 95% CI 1.12‐11.79 and OR 2.38, 95% CI 1.32‐4.29, respectively). Maternal and neonatal adverse events did not differ between groups. Conclusions Misoprostol vaginal insert proved to shorten the time to vaginal delivery and to reduce the use of other methods of labor induction and augmentation, but it did not reduce the cesarean section rate compared with oral misoprostol. The benefit of more rapid delivery associated with misoprostol vaginal insert should be weighed against the greater risks for uterine hyperstimulation and meconium‐stained amniotic fluid.

Oral misoprostol solution in comparison to vaginal misoprostol for induction of labour in a randomized controlled trial

“…This was not in consistence with finding by many studies. [23][24][25] While Mahajan study in 2018 had the same finding as the current study. 18 This could be explained as well as expected as different dosage regimen between these studies and this study.…”

Tachysystole and risk of cesarean section after labor induction using misoprostol: A cohort study

“…However, compared to other means of induction of labor, increased rates of tachysystole with misoprostol vaginal inserts (MVI) have been reported by several authors. [2][3][4] Presence of tachysystole during induction of labor is a concern as it is feared to lead to fetal blood deoxygenation due to decreased placental perfusion. 5 This in turn could lead to non-reassuring fetal heart traces, fetal acidosis, and hence higher rates of medical intervention and poorer neonatal outcomes.…”

“…5 Despite the high frequency of tachysystole after induction of labor with MVI, no difference in cesarean section rate or neonatal outcome has been observed between MVI and other induction methods. [2][3][4] Currently, there is conflicting evidence regarding the clinical impact of tachysystole, as some authors have reported an increase in cesarean section rates, operative vaginal delivery and neonatal morbidity [6][7][8] while others found no significant differences. [9][10][11] More information is therefore needed on the association between tachysystole and progression to cesarean section.…”

Efficacy and safety of Misoprostol vaginal insert to induce labor beyond 40 + 0 weeks of gestation

“…Prostaglandins have been proven to induce labor whilst not increasing the rate of cesarean sections (CS) among women with unscarred uterus [7]. [8][9][10][11][12][13] even for women with an unfavourable cervix as to BISHOP scores [14], while reducing the need for oxytocin compared to dinoprostone vaginal insert or oral misoprostol [8,10,15].…”

“…Hyperstimulation syndrome requiring tocolysis is more common in women receiving MVI [8,10,11,14,16].…”