Folic acid (or folate) is well known as a nutrient important for the prevention of birth defects. Newer research also shows that folic acid supplementation may help reduce the risk of preeclampsia. Preeclampsia is a condition in pregnancy (occuring after 20 weeks gestation) of high maternal blood pressure and urine proteins. Preeclampsia increases the risk of storke, kidney problems and premature birth.
Research reviewed folic acid intakes and pregnancy outcomes of approximately 3,000 Canadian women. Folic acid supplementation taken during the early second trimester and throughout pregnancies was associated with a lower rate of preeclampsia. Preeclampsia occured in 2.2% of women who took folic acid containing multivitamins compared to 5.1% of women who did not. Overall, a 63% reduction in the risk of preeclampsia was observed.
In a separate study, women in the Unted States were half as likely to develop preeclampsia if their vitamin D status was higher. After adjustment for other risk factors, increased vitamin D status* reduced the risk of preeclmapsia by one half. The authors concluded, "Vitamin D supplementation in early pregnancy should be explored for preventing preeclampsia and promoting neonatal well-being."
*blood level increase of 50 nmol/L
Wen and others. "Folic acid supplementation in early second trimester and the risk of preeclampsia." Am J Obstet Gynecol. 2008:45e1-e7.
Bondnar and others. "Maternal vitamin D deficiency increases the risk of preeclampsia." J Clin Endocrinol Metab, 2007 Sept;92(9):3517-22.