Optimizing periconceptional and prenatal folic acid supplementation

INTERVENTION: This is a two‐arm comparison study: PregVit‐Folic 5® (arm 1) contains 5 mg folic acid and PregVit® (arm 2) contains 1.1 mg folic acid. All other vitamin and mineral doses are identical between the 2 supplements. Both supplements are taken as 2 tablets daily, one tablet in the morning (am) and one tablet in the evening (pm). Both multivitamins are appropriate for periconceptional, prenatal, and post‐partum supplementation. For the single dose study, only 1 dose was taken. For the multiple dose study, supplementation continued for 30 weeks. CONDITION: Multivitamin supplementation in pregnancy ; Pregnancy and Childbirth ; Multivitamin supplementation in pregnancy PRIMARY OUTCOME: 1. To assess the serum folate pharmacokinetics in healthy, non‐pregnant women of childbearing age who ingest a single evening dose of PregVit‐folic 5® (5 mg folic acid) versus a single evening dose of PregVit® (1.1 mg folic acid).; 2. To assess steady‐state red blood cell and serum folate levels achieved in healthy, non‐pregnant women of childbearing age who supplement daily for 30 weeks with PregVit‐folic 5® versus PregVit®.; 3. To assess the steady‐state periconceptional and gestational red blood cell and serum folate levels in women planning a pregnancy or early in pregnancy (<6 weeks gestation) who supplement daily with PregVit‐folic 5® versus PregVit®.; ; For the single dose study, extensive blood sampling was conducted over 12 hours.; ; For the multiple dose study, blood sampling was conducted as follows:; ; Return to research site at 6 weeks gestation to draw one blood sample. Pick up next supply of multivitamins (hospital pharmacy).; ; Return to research site at 12 weeks gestation to draw one blood sample. Pick up next supply of multivitamins (hospital pharmacy).; ; Return to research site at 30 weeks gestation to draw last blood sample. SECONDARY OUTCOME: To assess adherence and tolerability of the prenatal mutlivitamins INCLUSION CRITERIA: Women planning a pregnancy, or women less than 6 weeks pregnant who are not using a prenatal mutlivitamin