Comparison of Nifedipine and Magnesium Sulfate in the Treatment of Preterm

Document Type : Original Article


1 Assistant Professor of Obstetrics & Gynecology, Mashhad University of Medical Sciences, Mashhad, Iran.

2 Resident of Obstetrics & Gynecology, Mashhad University of Medical Sciences, Mashhad, Iran.


Introduction:Premature delivery is the leading cause of perinatal morbidity and mortality. The early treatment and delaying of premature labor results in the increase in the survival of infant, improved quality of life and decrease in the cost of care of the premature neonate. In this study we have compared the safety, efficacy, side-effects and the cost of nifedipine and magnesium sulfate in treatment of preterm labor.
Methods: In this clinical-trial study, 80 pregnant women experiencing preterm labor at 26-34 weeks of gestation who referred to obstetric clinic of Imam Reza and Ghaem hospitals were enrolled from 2007 to 2008.(regular uterine contractions with periods less than 10 minutes with effacement and dilatation that did not respond to bed rest, fluid therapy and pethidine)The patients received either oral nifedipine or intravenous magnesium sulfate. The efficacy and side effects related to nifedipine and magnesium sulfate were recorded. All data were analyzed by SPSS software, using t student, chi-squire and Fischer exact tests.
Results: The response to tocolytic effects of the two drugs showed no significant difference within 48 hours and seven days of treatment (P=0.494), but the maternal side effects of nifedipine were significantly lower than the magnesium sulfate group (P=0.003).The mean cost of treatment was 13 times higher in the magnesium sulfate group than the nifedipine group and the difference was significant (P=0.001).
Conclusion: According to our study, we can conclude that the oral nifedipine may be a suitable alternative to magnesium sulfate as a tocolytic due to its good efficacy, minimal side effects, low cost and easy route of administration in the prevention of progress of premature labor.


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