The Effect of Topical Magnesium Sulfate during the Latent Phase of Labor on Cervical Effacement, Dilation, and Labor Duration between Primiparous and Multiparous Women: A Double-Blind Randomized Controlled Trial

Background & Objective: Cervical effacement and dilation are critical components in the progression of labor. Impairments in this process may disrupt the natural course of labor and lead to adverse maternal and neonatal outcomes. This study was conducted with aim to evaluate the effect of topical magnesium sulfate on cervical effacement, dilation, and fetal descent during the latent phase of labor.Materials & Methods: This double-blind randomized controlled trial was conducted on 101 term pregnant women (nulliparous and multiparous) divided into intervention and placebo groups. The intervention consisted of applying 10 mL of 50% magnesium sulfate solution (up to two doses) topically to the cervix during vaginal examination in the latent phase of labor. Cervical changes and labor outcomes were assessed at baseline and at 2- and 4-hours post-intervention.Results: No significant differences were observed between the groups in baseline maternal age. In nulliparous women, cervical dilation at 2 and 4 hours after intervention was significantly higher in the magnesium sulfate group compared to placebo (P=0.03 and P=0.01, respectively). Similarly, effacement was significantly greater at both time points (P=0.001 and P=0.007). Although a statistically significant increase in cervical dilation was not observed in multiparous women, labor duration was significantly shorter in both parity groups receiving magnesium sulfate compared to controls (P