Oral nifedipine versus intravenous labetalol for severe hypertension during pregnancy: a systematic review and meta-analysis.

BACKGROUND: Oral nifedipine is recommended along with labetalol and hydralazine for treatment of severe hypertension during pregnancy by most authorities. Although nifedipine is cheap and easily administered, the usage pattern among health care providers suggests a strong preference for labetalol despite lack of evidence for the same.

OBJECTIVES: To determine the efficacy and safety of oral nifedipine for treatment of severe hypertension of pregnancy compared with intravenous labetalol.

SEARCH STRATEGY: We systematically searched for articles comparing oral nifedipine with intravenous labetalol for the treatment of severe hypertension during pregnancy in any language, over Medline, Cochrane Central Register of Clinical Trials and Google Scholar from inception till February 2014.

SELECTION CRITERIA: We included all RCTs that compared intravenous labetalol with oral nifedipine for treatment of severe hypertension during pregnancy, addressing relevant efficacy and safety outcomes.

DATA COLLECTION AND ANALYSIS: Eligible studies were reviewed, and data were extracted onto a standard form. We used Cochrane review manager software for quantitative analysis. Data were analysed using a fixed effect model.

MAIN RESULTS: The pooled analysis of seven trials (four from developing countries) consisting of 363 woman-infant pairs showed that oral nifedipine was associated with less risk of persistent hypertension (RR 0.42, 95% CI 0.18-0.96) and reported maternal side effects (RR 0.57, 95% CI 0.35-0.94). However, on sensitivity analysis the outcome 'persistent hypertension' was no longer significant. Other outcomes did not reach statistical significance.

CONCLUSION: Oral nifedipine is as efficacious and safe as intravenous labetalol and may have an edge in low resource settings.

TWEETABLE ABSTRACT: Although studies to date are few in number and small, nifedipine shows promise for severe hypertension in pregnancy.