The comparison of the efficacy of nifedipine with ritodrine, nitroglycerine and magnesium sulfate for the management of preterm labor: systematic review and meta-analysisRunning Title: Tocolysis for management of preterm labor

Background: Some studies compared the efficacy of nifedipine with other drugs in treatment of preterm labor but the reported results is conflicting.Objective: This systematic review and meta-analysis aimed to compare the efficacy of nifedipine with ritodrine, nitroglycerine and magnesium sulfate for the management of preterm labor.Materials and methods: published articles until October ۲۴ ۲۰۲۲ were performed in in PubMed/Medline, Scopus, Web of Science, and Google Scholar for randomized controlled trials (RCTs) of tocolytic drugs interventions on preterm labor included in our study. Results: This meta-analysis which examines the status of preterm labor for more than a week including twenty-nine studies, prolongation in preterm delivery was significantly ۵% more in nifedipine compared to other tocolytic drugs (risk difference, ۰.۰۵; ۹۵% confidence interval, ۰.۰۱ to ۰.۰۹). Subgroup analysis showed that this difference was due to differences between nifedipine and ritodrine (risk difference, ۰.۱۱; ۹۵% confidence interval, ۰.۰۴ to ۰.۱۹)Conclusions: In general, the results of the present study showed that nifedipine is more effective than magnesium sulfate in postponing preterm labor for up to one week. However, this drug was equally effective in postponing preterm birth compared to other tocolytics including nitroglycerin and ritodrine during this period.On the other hand, based on the findings of this meta-analysis, the effectiveness of nifedipine for long-term prevention of preterm birth for more than one week was more than ritodrine but equal to magnesium sulfate and nitroglycerin.

Keywords:

nifedipine , nitroglycerine , magnesium sulfate , Ritodrine , preterm labor , tocolysis , systematic review , meta-analysis