Role of adding Isosorbide-5-Mononitrate to misoprostol in Induction of the second trimesteric abortion, a randomized controlled trial

Objective: To compare the therapeutic efficacy of prostaglandins when they used alone versus a combination therapy of prostaglandins and a nitric oxide (NO) donor as isosorbide-5-mononitrate to induce cervical ripening and effacement for induction of the second trimester missed abortion and occurrence of complete abortion. Methods: A Randomized clinical trial study in which 160 Second trimester (13-26weeks) missed abortion pregnant women admitted for medical induction of abortion, were randomly divided into two group (80 patients in each). One group received only vaginal Misoprostol and the other group received combined vaginal Misoprostol with Isosorbide-5-mononitrate. To determine the efficacy in form of " induction abortion interval ": the duration interval between the beginning of the induction and the complete expulsion of the abortus and also the number of the doses of misoprostol needed to complete expulsion and also the adverse events that increased or newly discovered when prostaglandins and a nitric oxide donor used together such as severe bleeding, headache, abdominal pain, pelvic pain, sever hypotension, backache, fever, nausea and vomiting. Results: It is proved in the study that combination between misoprostol and isosorbide mononitrate gives better results regarding cervical consistency improvement, cervical dilatation, effacement, the whole induction time and the number of misoprostol doses needed to complete expulsion when compared to misoprostol alone and also fewer side effects as abdominal pain. Conclusion: Misoprostol is a good cervical ripening agent when used alone but we can get a benefit from combining both misoprostol and NO donor (isosorbide-5- mononitrate) making a synergistic action with fewer side effects.