Isosorbide Mononitrate a Nitric Oxide Donor: A Study of Its Efficacy and Safety as an Agent for Cervical Ripening

In a study of 150 cases, mean maternal age was 22.2 ± 2.6 years (range 19–35 years) and mean gestational age was 40.5 ± 1.07 (range 40–42 weeks). 52 women were primigravidas, while 98 were multigravidas. The mean Bishop Score—before drug administration was 1.94 ± 1.3 (range 0–5), and mean fetal heart rate was 137 ± 6.2 bpm. The mean of Bishop scores before IMN administration was 1.94 ± 1.3, while mean of Bishop score after drug administration was 6.7 ± 2.2; mean difference was equal to 4.76. P value was equal to 0.0001. By conventional criteria, this difference is considered to be statistically significant. The mode of delivery 96 (64 %) delivered vaginally, while 54 (36 %) were delivered by Cesarean section. Mean Apgar score at 1 min was 8.2 ± 0.9 SD (range 7–10), while mean Apgar score at 5 min was 9.4 ± 0.6 (range 8–10). The only side effect noted was headache, and 30 cases (20 %) complained of headache.