Nifedipine compared to magnesium sulfate for treating preterm labor: A randomized clinical trial

Background: Preterm labor is the leading cause of infant morbidity and mortality so it may be necessary to administer tocolytics for treatment of it. Objective: The aim of this study was to compare the efficacy and safety of magnesium sulfate and nifedipine in the management of preterm labor. Materials and Methods: 100 women with documented preterm labor were randomly assigned to receive magnesium sulfate (n=50) and nifedipine (n=50) as tocolytic therapy. Before tocolysis, patient did not receive any sedation. After tocolysis, if patient continued to have contractions, they received other tocolytic agents. The main outcome variables examined were days gain in utero, success rate and side effects of tocolysis. Results: Both drugs were equally effective in prevention of labor and delaying delivery > 7 days, 56% vs. 64% in the nifedipine and magnesium sulfate groups, and the days gain in utero was no statistically different in two groups. 6% of nifedipine group and 2% of magnesium sulfate group required drug discontinuation due to severe symptoms. There were also no significant differences in maternal characteristics between two groups. The total success rate and side effects were similar in two groups. Conclusion: Oral nifedipine could be a suitable alternative for magnesium sulfate with the same efficacy and side effects in the management of preterm labor.