Vitamin D may reduce preeclampsia risk

A new study suggests that increased intakes of vitamin D during pregnancy may reduce the development of preeclampsia by about 25%.

In a study in over 20,000 Norwegian women, the risk of this potentially fatal condition was 27% lower in women who consumed vitamin D supplements with daily doses of 10 to 15 micrograms (mcg), compared to women who did not take supplements (1). The women answered a general health questionnaire at the fifteenth week of pregnancy and again at the thirtieth week, while a food frequency questionnaire was administered at week 22.

These findings are consistent with other reports of a protective effect of vitamin D on preeclampsia development. As a correlation between vitamin D intake and omega-3 fatty acid intake was observed, the researchers commented that further research is needed to disentangle the separate effects of these nutrients.

Preeclampsia, affecting 2–3% of all pregnancies, occurs when a mother's blood pressure rises to the hypertensive range, and excretion of protein in the urine becomes too high. It is estimated to be responsible for about 60,000 deaths worldwide. It is not known why some expectant mothers develop preeclampsia, although oxidative stress has been proposed to play a part.

1. Haugen M. et al. Vitamin D Supplementation and Reduced Risk of Preeclampsia in Nulliparous Women. Epidemiology, 2009; 20(5):720–726.