Folic Acid Supplementation in Pregnant Women: Dose Response

The proposed study is a double-blind randomized controlled trial in healthy pregnant women (BMI 18.5 - 29.9 kg/m2, age 18 - 40 yr) receiving prenatal care at Athens Regional Midwifery clinic (ARMC). The primary goal of the proposed study is to determine relative changes in blood folate and DNA methylation levels in response to 2 different supplemental doses of folic acid one of which will provide the Institute of Medicine's recommended folate intake for pregnant women and the second will provide a higher dose as routinely taken by pregnant women in over-the-counter prenatal supplements. The specific aims of the study are: 1. to compare maternal serum and red blood cell (RBC) folate levels and % change in women taking either 400 or 800 mcg/day of supplemental folic acid from the first prenatal visit (\< 10 weeks) through delivery; 2. to compare the infant's cord blood folate levels in response to different maternal folic acid intakes (400 mcg/d vs 800 mcg/d); 3. to determine relative differences in the levels of oxidized folic acid in maternal and infant blood in response to 400 or 800 mcg/d folic acid dose, and 4. to determine genome wide and gene specific DNA methylation response in pregnant women receiving prenatal supplements containing either 400 or 800 mcg folic acid per day