Effect of L-arginine supplementation on blood pressure in pregnant women: a meta-analysis of placebo-controlled trials.

OBJECTIVE: A meta-analysis of placebo-controlled trials was conducted to evaluate the effect of L-arginine supplementation on blood pressure (BP) in pregnancy. METHODS: Trials were searched in PubMed, Embase, and Cochrane Library. A total of five trials were included in the meta-analysis. RESULTS: L-arginine supplementation exhibited a mean decrease of 3.07 mmHg (p = 0.004) for diastolic blood pressure and a mean increase of 1.23 weeks (p = 0.002) for gestation age at delivery in pregnancy, but did not reduce systolic BP (p = 0.19) as compared to placebo. CONCLUSION: L-arginine supplementation had a significant effect of lowering diastolic blood pressure and prolonging gestation age in pregnancy.