Background: Cervical ripening prior to fetal expulsion may be induced by the metabolic activity of endogenous nitric oxide (NO) and the medical use of nitro vasodilatory medications such as isosorbide dinitrate. In order to manage second trimester missed abortions, we set out to compare the therapeutic efficacy and safety of isosorbide dinitrate versus misoprostol.

Methods: This prospective, double-blind, clinical trial was conducted at the department of obstetrics & gynecology at Zagazig university hospitals, Sharkia, Egypt, on 70 women having missed abortion between the 14-20 weeks of gestation. Patients were divided into two groups: Group (1): 35 women with missed abortion gestational age (GA) (14-20) received isosorbide dinitrate 80 mg = 4 tab., n = 35) and Group (2): 35 women with missed abortion GA (14-20) received misoprostol (100 mcg = ½ tab, n = 35).

Results: Both groups showed accepted success rate; Dinitrate success rate was 74.3% and Misoprostol success rate was 85.7% without any statistically significant difference between both groups. The symptoms of post-induction complications were comparable in both groups. Headache was the most frequent complication in dinitrate group 20% while abdominal pain was the most frequent complication in Misoprostol 8.6 %.

Conclusion: The findings of this study can offer a valuable insight aimed to enhancing counselling and support for isosorbide dinitrate compared to misoprostol in management of second trimester abortion. However, Isosorbide dinitrate is associated with significant side effects more than misoprostol as tachycardia, hypotension.