A dose-finding study of oral misoprostol for labor augmentation

Published:March 07, 2011DOI:


      We designed a dose-finding trial of oral misoprostol administered for labor augmentation.

      Study Design

      Healthy, nulliparous women in active labor and diagnosed with arrest of dilation were enrolled in cohorts of 10 at a time. Five regimens were studied: (1) 25 μg every 4 hours, (2) 50 μg every 4 hours, (3) 100 μg every 4 hours, (4) 50 μg every 2 hours, and (5) 75 μg every 4 hours.


      A total of 46 women were enrolled. Baseline uterine activity approximately doubled with 4 of the regimens and tripled with the highest dosage regimen (100 μg) (P < .001). The 100-μg regimen was truncated due to excessive uterine hyperstimulation (40%).


      An oral dose of 75 μg of misoprostol given at a 4-hour interval for a maximum of 2 doses is the highest tolerated dose. Randomized, controlled trials will be required before a regimen is employed routinely.

      Key words

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