Role of isosorbide mononitrate as an agent for cervical ripening in second-trimester abortions

Abstract

Objective: To compare the effectiveness and safety of isosorbide mononitrate (IMN), misoprostol (MP), and mechanical dilatation (MD) for cervical ripening in second-trimester abortions. Methodology: The present study was conducted in the Department of Obstetrics and Gynaecology, MGM Medical College, Indore, Madhya Pradesh, from September 2014 to August 2015. One-hundred and fifty women who had a valid indication for termination were included after informed consent and randomized into three groups of 50 each. Women with hypotension BP 8 mm were excluded. Results: In the study, indications for termination were fetal conditions (14.6%), maternal conditions (19.3%), contraceptive failure (39.3%), IUFD (16.6%), and others (10%). The mean ± SD of Bishop score before and after IMN were 1.18 ± 1.43 and 4.54 ± 1.70, whereas for MP, 1.2 ± 1.525 and 4.76 ± 1.80, and for MD, 1.3 ± 1.46 and 4.36 ± 1.56, respectively (p = 0.000 significant). The mean ± SD of induction ripening interval of 10.9 ± 3.23, 9.76 ± 3.17, and 12.92 ± 2.65 for IMN, MP, and MD (p = 0.000) shows that it was least for MP followed by IMN and MD. Comparison of induction–abortion interval showed mean ± SD of 28.32 ± 9.84, 29.00 ± 7.22, and 38.76 ± 9.87 for IMN, MP, and MD, respectively (p = 0.000). All cases of IMN and MP aborted vaginally; in MD group, 4% had a hysterotomy. Side effects were minimal in IMN group with only headache which was tolerable. Conclusion: IMN when compared with MP and MD proved to be a good cervical ripening agent for second-trimester abortions. It is safe, effective, and has minimum side effects. More studies are required for establishment of IMN as a ripening agent.