Comparative Study of Misoprostol in First and Second Trimester Abortions by Oral, Sublingual, and Vaginal Routes

To identify an effective misoprostol-only regimen for termination of pregnancy between 12 and 20 weeks of gestation, a prospective randomized study comparing sublingual, vaginal, and oral routes of administration of misoprostol was done.

One hundred and fifty women (12-20 weeks gestation) were randomly divided into three groups and given 400 mcg misoprostol sublingually, vaginally, and orally every 4 h up to a maximum of four doses. Primary outcome was the success rate at 24 h. Secondary outcomes were failure rate, induction-abortion interval, and need for surgical intervention. Various side effects and patients' subjective assessment of comfort with the route of administration were also studied.

Success rate at 24 h of sublingual (86 %) group was higher compared to oral (64 %) group (P = 0.011). Complete abortion rate of sublingual (76 %) group was higher than that of oral (48 %) group (P = 0.004). There was no significant difference in the failure rate and need for surgical intervention in the three groups. Induction-abortion interval in sublingual (9.8 ± 3.6 h) and vaginal (10.6 ± 2.9 h) groups was shorter than that in oral group (14.3 ± 3.3). Diarrhea occurred significantly more in the oral group (28 %) and sublingual (22 %) compared to vaginal group (6 %). Fever was significantly higher in vaginal (36 %) than that in the oral group (12 %). Oral route of administration was most comfortable.

Sublingual route results in significantly higher abortion rate compared to oral route. Vaginal route has efficacy similar to sublingual route.