This sheet is about exposure to folic acid in pregnancy and while breastfeeding. This information is based on published research studies. It should not take the place of medical care and advice from your healthcare provider.

What is folate?

Folate is the naturally occurring form of vitamin B9. Many foods contain folate, including dark leafy greens, asparagus, broccoli, avocados, beans, carrots, squash, nuts, and citrus fruits. Folate is important for making cells in the body and keeping cells healthy.

What is folic acid?

Folic acid is the lab-made form of vitamin B9 (folate). Folic acid is more stable than other forms of folate and doesn’t break down as easily in light or heat (such as cooking). Folic acid is available over the counter as a dietary supplement and is often found in prenatal vitamins. In the United States, folic acid and other B vitamins are added to some cereals, wheat flours, corn meal, rice, and many types of bread and pasta to increase their nutritional value. Many other countries also add folic acid to wheat and maize flours.

How much folic acid should I be taking?

It has been recommended that women who are able to get pregnant take 400 micrograms (mcg) (or 0.4 milligrams [mg]) of folic acid per day, whether they are planning a pregnancy (since not all are planned). Taking folic acid starting at least 1 month before pregnancy can lower the chance of some kinds of birth defects in early pregnancy, including neural tube defects (certain birth defects of the brain, spine, or spinal cord, such as spina bifida).

During pregnancy, the recommended amount of folic acid for most women is 600-800 mcg (0.6-0.8 mg) per day. Most women can get this amount by eating enough foods that have added folic acid and/or taking folic acid in a prenatal vitamin or as a separate dietary supplement.

In addition to recommended daily amounts, many nutrients also have upper intake levels, abbreviated as “UL.” UL is the highest level of daily intake recommended for most people. The UL for folic acid/folate is 1,000 mcg (1 mg) per day.

Some women are recommended to take more than 1,000 mcg (1 mg) of folic acid per day before and during pregnancy. These include some women with a family history of having a child with a neural tube defect. Extra folic acid might also be recommended for women who take certain medications, drink large amounts of alcohol, or have health conditions that affect how their bodies absorb nutrients. Talk with your healthcare provider about how much folic acid is right for you.

I take folic acid. Can it make it harder for me to get pregnant?

Folic acid is not expected to make it harder to get pregnant. It is recommended to take a daily supplement of folic acid at least one month before getting pregnant to help lower the chance of birth defects.

Does taking folic acid increase the chance of miscarriage?

Miscarriage is common and can occur in any pregnancy for many different reasons. Folic acid is not expected to increase the chance of miscarriage. Some studies suggest that taking folic acid in recommended amounts might help lower the chance of miscarriage.

Does taking folic acid increase the chance of birth defects?

Birth defects can happen in any pregnancy for different reasons. Out of all babies born each year, about 3 out of 100 (3%) will have a birth defect. We look at research studies to try to understand if an exposure, like folic acid, might increase the chance of birth defects in a pregnancy.

Taking folic acid in recommended amounts has not been found to increase the chance of birth defects. Taking folic acid before and during pregnancy lowers the chance of neural tube defects and might lower the chance of other birth defects.

Does taking folic acid increase the chance of other pregnancy-related problems?

Taking folic acid in recommended amounts is not expected to increase the chance of other pregnancy-related problems, such as preterm delivery (birth before week 37) or low birth weight (weighing less than 5 pounds, 8 ounces [2500 grams] at birth). Some studies suggest that taking folic acid might lower the chances of preterm delivery, high blood pressure during pregnancy, stillbirth, or infant death in the newborn period.

Does taking folic acid in pregnancy affect future behavior or learning for the child?

Taking folic acid in recommended amounts has not been found to increase the chance of behavior or learning issues for the child.

Breastfeeding and folic acid:

Folate is found naturally in the breast milk of women who are well-nourished. Babies who are exclusively breastfed get all their folate from breast milk, so it is important to get enough folate/folic acid while breastfeeding for the baby. It is recommended to get 500 mcg (0.5 mg) of folic acid per day while breastfeeding. Be sure to talk to your healthcare provider about all your breastfeeding questions.

If a man takes folic acid, could it affect fertility or increase the chance of birth defects?

Taking folic acid is not expected to affect men’s fertility (ability to make healthy sperm) or increase the chance of birth defects. In one study involving men being treated for infertility, taking folic acid supplements increased sperm motility (movement). The recommended amount of folic acid for most men is 400 mcg (0.4 mg) per day. Men can talk with their healthcare providers about the right amount of folic acid for them. For more general information on paternal exposures, see the MotherToBaby fact sheet at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.

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