Buccal versus intravaginal misoprostol administration for cervical ripening. Sublingual misoprostol for the induction of labor at term. Sublingual compared with oral misoprostol in term labour induction: a randomised controlled trial.
The purpose of this study was to compare the efficacy of misoprostol that is administered in the buccal pouch with the intravaginal route of administration.
                One hundred fifty-seven pregnant women with a singleton live gestation, Bishop score of <7, estimated fetal weight of <4500 g, and gestational age of >24 weeks were randomized to receive misoprostol that would be placed either in the buccal pouch or vagina every 6 hours. In the buccal group, after the first 2 doses of 200 microg, the dose was increased to 300 microg for the duration of the study (up to a total of 1600 microg). In the vaginal group, after the first 2 doses of 50 microg, the dose was increased to 100 microg for the duration of the study (up to a total of 500 microg). The primary outcome variable was the interval from the first dose to vaginal delivery. Power calculations indicated the need to enroll 71 patients in each arm of the study, which would allow for the detection of a 4-hour reduction in vaginal birth interval for buccal misoprostol.
                The hours from drug administration to vaginal delivery were similar between the buccal and vaginal groups (23.5 +/- 20.8 hours versus 21.3 +/- 13.4 hours), respectively. Thirty-five women (63%) versus 34 women (67%) delivered vaginally within 24 hours (P = not significant). The incidence of tachysystole was higher in the buccal group, 28 occurrences (38%) versus 15 occurrences (19%; P =.01).
                Buccal misoprostol is effective for cervical ripening but results in a higher incidence of tachysystole than does intravaginal administration. To evaluate the efficacy, safety, and patient acceptability of sublingual misoprostol compared with an equivalent dose administered orally for labor induction at term.
                One hundred women with medical or obstetric indications for induction of labor after 37 weeks of gestation and unfavorable cervices were randomized to receive 50 microg of misoprostol either orally or sublingually. The dose was repeated every 4 hours to a maximum of 5 doses if indicated. Previous cesarean delivery was a criteria for exclusion. Our primary outcome measure was the number of patients who went on to have a vaginal delivery within 24 hours of the induction. The need for oxytocin, mode of delivery, number of cesarean deliveries for fetal distress, uterine hyperstimulation rates, and neonatal outcomes were secondary outcome measures. Patient acceptability was assessed by questionnaires completed after delivery.
                Significantly more patients were delivered of infants within 24 hours (73.8% versus 45.7%; relative risk, 1.6; 95% confidence interval, 1.1 to 2.4) and the induction to delivery intervals were significantly shorter (20 hours versus 28.3 hours; mean difference, 8.3 hours; 95% confidence interval, 1.2 to 15.4) in the sublingual group compared with the oral group. There was 1 case of uterine hyperstimulation in the sublingual group. There were no significant differences in the mode of delivery, interventions for fetal distress, or neonatal outcomes in the 2 groups. The satisfaction rates were 82.5% and 85.7% in the oral and sublingual groups respectively, and 9.5% of patients thought that the sublingual tablets did not dissolve completely.
                There has been no previous report in the literature of misoprostol given sublingually for labor induction. Sublingual misoprostol seems to have better efficacy than oral misoprostol, seems to be acceptable to patients, and is an option to be considered to induce labor at term. To compare the efficacy and patient acceptability of 50 microg of sublingual misoprostol with 100 microg of oral misoprostol in the induction of labour at term.
                Non-blinded randomised comparative trial.
                Tertiary level UK Hospital.
                Two hundred and fifty women at term with indications for labour induction.
                Fifty micrograms of sublingual misoprostol or 100 microg of oral misoprostol was administered every four hours after random allocation, to a maximum of five doses.
                Number of patients delivering vaginally within 24 hours of the induction, mode of delivery, neonatal outcomes and patient acceptability.
                There was no significant difference in the number of women delivering vaginally within 24 hours of the induction in the sublingual group as compared with the oral group (62.8% vs 59%, RR 1.1, 95% CI 0.6-2.1), or in the mean induction to delivery time (21.8 vs 24.1 h, mean difference 2.3 h 95% CI -2.2 to +6.7). There was no difference in the uterine hyperstimulation rates (1.6% in both groups), operative delivery rates or neonatal outcomes. In the sublingual group, 92.6% found the induction acceptable with 15.8% finding the tablets with an unpleasant taste, while in the oral group it was 96.9% and 4%, respectively. More patients in the oral group thought that they would consider the same method of induction again as compared with the sublingual group (58.6% vs 40%, RR 1.4, 95% CI 1.04-1.9).
                Fifty micrograms of sublingual misoprostol every four hours has the same efficacy and safety profile as compared with 100 microg orally, but the oral route might be preferred by women.
Based on only three small trials, sublingual misoprostol appears to be at least as effective as when the same dose is administered orally. There are inadequate data to comment on the relative complications and side-effects. Sublingual or buccal misoprostol should not enter clinical use until its safety and optimal dosage have been established by larger trials.
[Note: The 17 citations in the awaiting classification section of the review may alter the conclusions of the review once assessed.]