Comparison of Administration of Magnesium Sulfate and Nifedipine in Prevention of Preterm Delivery

Document Type : Original Article


1 Assistant Professor of Obstetrics and Gynecology, Semnan University of Medical Sciences, Semnan, Iran.

2 Associate Professor of Social Medicine, Semnan University of Medical Sciences, Semnan, Iran.

3 Resident in Obstetrics & Gynecology, Semnan University of Medical Sciences, Semnan, Iran.


Introduction: Preterm labor is one of the main problems in obstetrics and gynecology medicine. Premature newborn may have numerous physical and mental disorders. The aim of this study is to compare the effects of magnesium sulfate with Nifedipine in order to prevent the preterm labor.
Methods: In this clinical trial, 130 preterm labored women with gestational age of 20-37 weeks were enrolled and divided into two groups regarding their age (±3years), meantime between symptoms and treatment (±2 hours) and gestational age. The exclusion criteria were diabetes mellitus, hypertension, twin pregnancy, cigarette smoking and cervical incompetence. Magnesium sulfate was used with loading dose of 4g/IV and then maintanance of 2g/h and oral Nifedipine was applied by 20 mg as first dose and then 20 mg every six hours up to 24 hours. The duration between initiation of drugs and their therapeutic effects in subsiding the preterm labor pains were evaluated and data were analyzed by Kolmogorov-Smirnov, t and Mann-Whitney U tests and the statistical significance of 0.05 were considered for analysis.
Results: The difference of means of intervals between treatment and pain relief in Magnesium Sulfate (15.86±14.72 min) and Nifedipine (14.32±15.39 min) were significant (P=0.01). There were no significant difference between two groups in meantime of initiation of treatment and pregnancy termination (P=0.47).
Conclusion: Regarding the findings of current study, it seems that Nifedipine is more effective than magnesium sulfate in prevention of preterm labor.


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