Misoprostol vaginal insert and time to vaginal delivery: a randomized controlled trial

Area of Science:

• Obstetrics and Gynecology
• Reproductive Medicine
• Clinical Pharmacology

Background:

• Labor induction is a common obstetric procedure.
• Dinoprostone has been a standard agent for cervical ripening and labor induction.
• Alternative agents are being investigated to improve induction efficiency and patient outcomes.

Purpose of the Study:

• To compare the efficacy and safety of a 200-microgram misoprostol vaginal insert versus a 10-mg dinoprostone vaginal insert for labor induction.
• To evaluate the impact of each agent on time to vaginal delivery, cesarean delivery rates, and other key obstetric outcomes.

Main Methods:

• A phase III, double-blind, multicenter, randomized study.
• 1,358 women with a modified Bishop score of 4 or less were assigned to receive either misoprostol or dinoprostone vaginal inserts.
• Coprimary end points included time to vaginal delivery and cesarean delivery rate.

Main Results:

• Misoprostol significantly reduced median time to vaginal delivery (21.5 vs. 32.8 hours, P<.001).
• Time to any delivery, time to active labor, and need for oxytocin were also significantly reduced with misoprostol.
• Cesarean delivery rates were comparable (26.0% vs. 27.1%), but uterine tachysystole was more frequent with misoprostol (13.3% vs. 4.0%, P<.001).

Conclusions:

• The 200-microgram misoprostol vaginal insert is effective in shortening labor induction times compared to dinoprostone.
• Misoprostol use resulted in a decreased need for oxytocin augmentation.
• While cesarean rates were similar, increased monitoring for uterine tachysystole is warranted with misoprostol.