Vitamin D, aspirin, exercise reduce pregnancy-related hypertension

There appears to be several ways to reduce the risk of pre-eclampsia and pregnancy-induced hypertension. These include low molecular weight heparin (LMWH), vitamin D supplementation, calcium supplementation, aspirin, and exercise, according to a meta-analysis.

Researchers explored multiple electronic databases for randomized controlled trials that compared prophylactic strategies for pre-eclampsia with each other or with negative controls. Two reviewers independently extracted data, evaluated the risk of bias, and assessed evidence certainty. Frequentist and Bayesian network meta-analysis models were applied in the analyses.

A total of 130 trials involving 112,916 patients were included in the analysis. These studies covered 13 prophylactic strategies. Pooled data revealed the following strategies as beneficial in the prevention of the composite primary outcome of pre-eclampsia and pregnancy-induced hypertension: LMWH (relative risk [RR], 0.60, 95 percent confidence interval [CI], 0.42–0.87), vitamin D supplementation (RR, 0.65, 95 percent CI, 0.45–0.95), and exercise (RR, 0.68, 95 percent CI, 0.50–0.92).

All three strategies proved as good as aspirin (RR, 0.79, 95 percent CI, 0.72–0.86) and calcium supplementation (RR, 0.71, 95 percent CI, 0.62–0.82) in preventing pre-eclampsia and pregnancy-induced hypertension. The rankings, according to p-score, were as follows: LMWH (85 percent), vitamin D (79 percent), exercise (76 percent), calcium (74 percent), and aspirin (61 percent).

Head-to-head comparison showed no differences across the evaluated prophylactic strategies, except for exercise, which tended to be superior to aspirin and calcium supplementation with respect to preventing pregnancy-induced hypertension.

The prophylactic effects of aspirin and calcium supplementation were consistent across subgroups. Meanwhile, the prophylactic effects of LMWH, exercise, and vitamin D supplementation on pre-eclampsia and pregnancy-induced hypertension varied with the different risk populations, dosages, and areas, among others. The certainty of the evidence was moderate to very low.