Antioxidants Didnt Reduce Pregnancy-Related Hypertension

PITTSBURGHVitamin C and E supplementation starting in the ninth to 16th week of pregnancy did not reduce the rate of pregnancy-associated hypertension in mothers or their children in a National Institute of Child Health and Human Development (NICHD) study (NEJM 2010 April 8).

Because oxidative stress has been proposed as a mechanism of action causing preeclampsia, a condition in which high blood pressure and protein in the urine develop after the 20th week of pregnancy, researchers hypothesized antioxidant supplementation with vitamins C and E, initiated early in pregnancy, could reduce the risk of serious adverse maternal, fetal and neonatal pregnancy-associated hypertension.

University of Pittsburgh researchers conducted a multicenter, randomized, double blind trial involving 10,000 women who were pregnant with their first child and who were at low risk for preeclampsia. Women were randomly assigned to begin daily supplementation with 1,000 mg of vitamin C and 400 IU of vitamin E or matching placebo between the ninth and 16th weeks of pregnancy. The two groups were similar with respect to baseline characteristics and adherence to the study drug.

The researchers found no significant difference between the vitamin and placebo groups in the rates of severe pregnancy-associated hypertension alone ,or severe or mild hypertension with elevated liver-enzyme levels, thrombocytopenia, elevated serum creatinine levels, eclamptic seizure, medically indicated preterm birth, fetal-growth restriction or perinatal death. Additionally, no significant differences were found between the groups in the rates of preeclampsia or adverse perinatal outcomes.