Nitric oxide donors for cervical ripening in first-trimester surgical abortion

Isosorbide Mononitrate Versus Dinoprostone for Cervical Ripening During Labor Induction: a Systematic Review and Meta-analysis of Randomized Controlled Trials

The objective of this study was to conduct a systematic review and meta-analysis of all randomized controlled trials (RCTs) that evaluated isosorbide mononitrate (ISMN) versus dinoprostone, a prostaglandin E2 (PGE2) analogue, in promoting cervical ripening during labor induction. We searched five major databases from inception till 02 May 2021. We assessed the risk of bias of included studies. We meta-analyzed various endpoints (n=12) and pooled the endpoints as mean difference (MD) or risk ratio (RR) with 95% confidence interval (CI). Overall, 4 RCTs met the inclusion criteria, comprising 818 patients; equally 409 patients were allocated to ISMN and PGE2 groups. Overall, the RCTs had a low risk of bias. The mean change in Bishop score at 24 h was significantly lower in disfavor of the ISMN group. The mean time from drug administration to delivery was significantly longer in disfavor of the ISMN group. The rate of oxytocin need was significantly higher in disfavor of the ISMN group. The rate of vaginal delivery at 24 h was significantly lower in disfavor of the ISMN group. The rates of headache and palpitations were significantly higher in disfavor of the ISMN group. The rate of abnormal fetal heart rate was significantly lower in favor of the ISMN group. There was no significant difference between both groups with regard to rates of cesarean delivery, postpartum hemorrhage, uterine hyperstimulation, and NICU admission. Compared with PGE2, ISMN appeared less effective for cervical ripening prior to labor induction and correlated with higher drug-related maternal toxicities.

Misoprostol plus isosorbide mononitrate versus misoprostol alone for cervical ripening during labor induction: A systematic review and meta-analysis of randomized controlled trials

AIM

To conduct a systematic review and meta-analysis of all randomized controlled trials (RCTs) that examined the maternal and neonatal outcomes of misoprostol+isosorbide mononitrate (ISMN) versus misoprostol alone (control) in promoting cervical ripening during labor induction.

METHODS

We searched five databases from inception until 05-May-2021. We assessed risk of bias of RCTs, meta-analyzed 23 endpoints, and pooled them as mean difference or risk ratio with 95% confidence interval.

RESULTS

Overall, five RCTs met the inclusion criteria, comprising 850 patients (426 and 424 patients were allocated to misoprostol+ISMN and misoprostol group, respectively). Overall, the RCTs had a low risk of bias. Pertaining to maternal delivery-related outcomes, there was no significant difference between both groups regarding the mean interval from drug administration to delivery, rate of vaginal delivery, rate of cesarean section delivery, and rate of need for oxytocin augmentation. Pertaining to maternal drug-related side effects, the rate of maternal headache was significantly higher in disfavor of the misoprostol+ISMN compared with misoprostol alone. However, the rates of maternal nausea, hypotension, flushing, palpitation, dizziness, postpartum hemorrhage, and uterine tachysystole did not differ between both groups. Pertaining to neonatal outcomes, there was no significant difference between both groups regarding rates of NICU admission, meconium-stained amniotic fluid, and Apgar score <7 at five minutes.

CONCLUSION

Compared with misoprostol alone, co-administration of misoprostol+ISMN did not correlate with superior maternal delivery-related outcomes. The rate of maternal headache was significantly higher in disfavor of the misoprostol+ISMN group. There was no significant difference between both groups regarding neonatal endpoints.