Why you need folic acid

If you're pregnant or might become pregnant, you need folic acid (vitamin B9) for a number of compelling reasons.

Folic acid helps prevent neural tube defects (NTDs)—serious birth defects of the spinal cord (such as spina bifida) and the brain (such as anencephaly). Neural tube defects occur at a very early stage of development, before many women even know they're pregnant. They affect about 3,000 pregnancies a year in the United States. 

The Centers for Disease Control and Prevention (CDC) reports that women who take the recommended daily dose of folic acid starting at least one month before conception and during the first trimester of pregnancy reduce their baby's risk of neural tube defects by 50 to 70 percent.

Some research suggests that folic acid may help lower your baby's risk of other defects as well, such as cleft lip, cleft palate, and certain types of heart defects.

Your body needs folic acid to make normal red blood cells and prevent a type of anemia. Folic acid is also essential for the production, repair, and functioning of DNA, our genetic map and a basic building block of cells. So getting enough folic acid is particularly important for the rapid cell growth of the placenta and your developing baby.

Some research suggests that taking a multivitamin with folic acid may reduce your risk of preeclampsia, a complex disorder that can affect your health and your baby's.

How much folic acid you need

To reduce your baby's risk of developing a neural tube defect, experts recommend that you take 400 micrograms (mcg) of folic acid per day, beginning at least a month before you start trying to get pregnant.

In fact, because half of the pregnancies in the United States are unplanned, the CDC, the U.S. Public Health Service, the March of Dimes, the American College of Obstetricians and Gynecologists (ACOG), and other experts strongly recommend that all women of childbearing age get 400 mcg of folic acid every day.

Some groups, such as the U.S. National Institutes of Health, suggest boosting your intake to at least 600 mcg daily once you're pregnant.

The neural tube—from which your baby's spine and brain develop – begins to form about three weeks after conception, so it's critical to get a sufficient daily dose of folic acid before conception and during the first trimester of pregnancy