Vaginal versus sublingual misoprostol for second-trimester pregnancy termination and effect on Doppler measurements.

Objective: To compare the efficacy of vaginal versus sublingual misoprostol for second-trimester pregnancy termination, and to evaluate the effect on the blood flow of the uterine and umbilical arteries.

Methods: Forty-nine patients were randomized to receive either 200 microg of vaginal misoprostol every 6 hours or 200 microg of misoprostol sublingually every 6 hours. Doppler velocimetry studies were assessed immediately before and 60 minutes after the administration of the first dose. Standard descriptive calculations, Mann-Whitney U, Wilcoxon, and chi(2) tests were performed.

Results: The mean interval between induction and onset of active labor, induction and delivery, and the duration of oxytocin administration were significantly shorter in the sublingual misoprostol group. Both routes of administration increased the Doppler indices for the uterine arteries; however, misoprostol via the sublingual route did not affect the umbilical arteries.

Conclusion: Sublingual administration of misoprostol for second-trimester medical abortion results in a higher success rate and does not affect umbilical blood flow.