Comparison of isosorbide mononitrate and misoprostol for cervical ripening in termination of pregnancy between 8 and 12 weeks: a randomized controlled trial

Abstract

Aim: The present study was undertaken to compare the efficacy of isosorbide mononitrate (IMN) and misoprostol for cervical ripening in termination of pregnancy between 8 and 12 weeks.

Materials and methods: This prospective randomized single blind study enrolled 40 women with singleton pregnancy seeking surgical termination of pregnancy between 8 and 12 weeks of gestation. They were divided into two groups--group I received IMN 40 mg while group II received misoprostol 40 mg vaginally, 3 h prior to suction and evacuation. All women were monitored for effects of cervical ripening and adverse effects.

Results: The mean sizes of dilators that could be negotiated without any resistance was 5.9 ± 1.33 in group I and 8.6 ± 0.94 in group II (p < 0.001, 95% CI 0.58, 0.41). The mean dilator sizes at which resistance was first encountered was 6.9 ± 1.37 in group I and 9.9 ± 1.23 in group II (p < 0.001, 95% CI 0.60, 0.54). The mean blood loss was 61.5 ± 13.86 ml in group I and 36.25 ± 12.80 ml in group II (p < 0.001, 95% CI 6.07, 5.63). Headache was the most common adverse effect seen with IMN use.

Conclusion: The results show that IMN has a definite role and better safety profile than misoprostol in first trimester cervical ripening, although misoprostol is more effective and causes less blood loss.