Comparing the effects of vaginal misoprostol and isosorbide mononitrate on cervical ripening in abortions under 20 weeks: a randomized controlled trial


  • Shahla Farzipour Department of Pediatrics, School of Medicine, Ardabil University of Medical science, Ardabil, Iran
  • Firouz Amani Department of Community Medicine, School of Medicine, Ardabil University of Medical science, Ardabil, Iran
  • Mahsa Rezaei School of Medicine, Ardabil University of Medical science, Ardabil, Iran



Misoprostol, Isosorbide mononitrate, Abortion, Cervical ripening


Background: In the first trimester of pregnancy, 15 to 20 percent of pregnancies result in miscarriage. Misoprostol is a widely medication that used for induction of labor in the second trimester; therapies, early termination of pregnancy and also used in duration of term delivery. The objective of this study was to comparing the effects of vaginal misoprostol and isosorbide menonitrate on cervical ripening in abortion under 20 weeks.

Methods: In this prospective randomized clinical trial, 120 pregnant women with miscarriage were enrolled in the study and randomly divided into 3 groups: vaginal misoprostol, isosorbide mononitrate and control group. The effect of all drugs on cervical dilatation and ripening, time needed for abortion, and also their side effects were evaluated.

Results: The mean of VAS in misoprostol group with 6.2±2.3 was significantly more than isosorbide mononitrate group with 3.4±1.5 and control group with 3.2±2.4. The rate of abortion in misoprostol group was significantly lower than other two groups. The change in dilation rate more than 3 cm in misoprostol group with 50% was significantly more than other two groups with 35% and 20%. Nausea, diarrhea, fever and bleeding rate were higher in the misoprostol group than other two groups. Headache in the isosorbide mononitrate group was significantly higher than the other groups.  

Conclusions: The results showed that we can use isosorbide mononitrate as a suitable alternative with better safety to vaginal misoprostol in cervical repining in abortions under 20 week.


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