Misoprostol for induction of labour: a comparative study of various routes of administration

Background: Oxytocin has been used for labor induction since very long, but with high rates of failed induction. The objective of this study is to compare the safety and efficacy of various routes of misoprostol for induction of labor at term. Design: Prospective randomized study was done at the department of obstetrics and Gynecology at the PGIMSR ESI Basaidarapur, New Delhi between August 2009 and July 2011.Methods: 150 pregnant women were randomized into three groups each to receive 50 mcg of Misoprostol via oral, sublingual and vaginal routes respectively. Doses were repeated 6 hourly for a maximum of 3 doses till the patient entered active stage of labor (clinically adequate contractions of 3/10 min of >40 s duration, and cervical dilatation of with 4 cm). Statistical analysis was done using chi-square test and ANOVA (one-way analysis of variance).Results: Mean number of dosage required for successful induction were significantly less in the vaginal group than oral and sublingual groups (in oral groups A were 2.1±0.42, sublingual 1.4±0.34, vaginal 1.1±0.29). The induction to delivery interval was significantly less in vaginal group than oral and sublingual groups (Group A oral 21.06±9.22 h, group B sublingual 16.81±8.08 h, group C vaginal 12.9±5.16 h 0.016 significant). Rate of caesarean was least in the vaginal group 12% vs 20% in oral and 26% in sublingual. All the three groups showed satisfactory neonatal outcomes.Conclusions: This study shows that vaginal route of administration of misoprostol is preferable to oral route and sublingual route for induction of labor when used in equivalent dosage of 50 mcg 6 hourly, however all three routes are well tolerated with favorable neonatal outcomes