Use of Nitric Oxide Donor Isosorbide Mononitrate for Cervical Ripening at 41 Weeks’ Gestation

Abstract

Background: The ideal agent for cervical ripening would induce adequate cervical ripening with minimal adverse effects to the mother and the fetus; the most favorable method for cervical ripening is not fully agreed till now; however, vaginal administration of isosorbide mononitrate (IMN) is considered a low-risk method of labor induction for post term. Our study was designed to assess the effect of IMN on cervical ripening and labor induction among 41 weeks pregnant women. Objectives: To assess the efficacy of the nitric oxide donor isosorbide mononitrate on cervical ripening at 41 weeks gestation. Materials and Methods: This study was conducted on 100 pregnant women recruited from the outpatient clinic fulfilling the inclusion criteria. Cases were divided into 2 groups. In first group 40 mg isosorbide mononitrate (IMN) tablet was applied vaginally in posterior fornix, and in second group placebo was applied vaginally in posterior fornix. Following up the cervical status after 24 hours of administration, the patient were asked about new symptoms especially headache, palpitation, dizziness or abdominal pain and the mode of delivery was assessed. Results: There was a significant improvement in the bishop score in the first group rather than the placebo group. No significant difference between the two groups was as regards the mode of delivery. Conclusion: IMN may be used for cervical preparation only before induction of labor in post term cases.