New therapies in the prevention of preeclampsia.

PURPOSE OF REVIEW: The review summarizes the results of recent randomized clinical trials whose primary purpose was to prevent preeclampsia and explores safety concerns that have been raised by these trials. Preeclampsia remains one the most common causes of perinatal and maternal mortality, particularly in resource-poor developing countries where its impact on morbidity and mortality is 20 to 100-fold greater than that in developed countries. The potential benefit of antioxidant vitamins and calcium continue to be explored, and are the subject of this review.

RECENT FINDINGS: Two large, prospective, randomized trials involving more than 4000 low and high-risk subjects, respectively, compared vitamin C/E to placebo. There were no differences noted in the frequency of preeclampsia between groups. Additionally, potential adverse influences of supplementation on low birthweight, late stillbirth, and severity and timing of preeclampsia and neonatal acidosis were noted. A large, multicenter calcium vs. placebo trial sponsored by the World Health Organization in locations known to have dietary calcium deficiency failed to reduce preeclampsia or low birthweight rates.

SUMMARY: These negative trials have reduced the likelihood that antioxidant or calcium supplementation will significantly impact the incidence of this disease. The safety concerns regarding antioxidants must be carefully explored.