Written By: IJCP Editorial Team

Published On: 27 Mar, 2025 12:05 PM | Updated On: 27 Mar, 2025 12:14 PM

Comparison of Maternal and Neonatal Outcomes in Labor Induction: 25 µg vs. 50 µg Oral Misoprostol

The current observational study evaluated maternal and neonatal outcomes with the use of 25 µg of oral Misoprostol administered every two hours versus 50 µg given every four hours for labor induction. The study included women with a viable singleton pregnancy between 37 and 42 weeks gestation who required labor induction with oral Misoprostol.

This retrospective cohort study analyzed anonymous data between 2016 and 2021, comparing the current protocol (25 µg every 2 hours from June 2018 to March 2021) with the previous protocol (50 µg every 4 hours from March 2016 to May 2018). The primary outcome was the rate of cesarean sections. Secondary outcomes included a composite neonatal outcome (Apgar score <7 at 5 minutes and/or NICU admission) and instances of uterine hyperstimulation.

The results revealed: 

• The study included 1,002 women: 621 received 25 µg and 381 received 50 µg of oral Misoprostol. 
• The composite neonatal outcome was significantly lower in the 25 µg group compared to the 50 µg group (adjusted odds ratio [aOR] 0.67, 95% CI 0.46–0.97). 
• There was no significant difference in cesarean section rates between the two groups (18.4% for 25 µg vs. 21.5% for 50 µg, aOR 0.74, 95% CI 0.52–1.05).
• Only one case of uterine hyperstimulation with fetal heart rate changes was reported in the 25 µg group, while none occurred in the 50 µg group (0.1).

In conclusion, the cesarean section rate remained unchanged between the two protocols. However, the use of 25 µg oral Misoprostol was linked to a significant reduction in the composite neonatal outcome. Low-dose oral Misoprostol may be a safe option for outpatient labor induction, but further research, particularly randomized controlled trials, is necessary.

Source: Wesselius SM, de Groot CJM, de Heus R, de Boer MA. Improved neonatal outcome following induction of labour using 25 µg versus 50 µg oral Misoprostol: A retrospective, comparative cohort study. J Gynecol Obstet Hum Reprod. 2025 Apr;54(4):102927. doi: 10.1016/j.jogoh.2025.102927. Epub 2025 Feb 13. PMID: 39954960.