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

What is folic acid?

Folic acid is available as a nutritional supplement. It is the lab-made form of the vitamin folate (vitamin B9). Folate is important for making and maintaining healthy cells in the body. The body has an easier time absorbing folic acid than folate.

Many foods contain folate. These foods include dark leafy greens, asparagus, broccoli, avocado, beans, carrots, squash, nuts, and citrus fruits. Folic acid is added to some foods to increase their nutritional value. In the United States, folic acid is added to cereal, wheat flour, corn meal, rice, and many types of bread and pasta. Many other countries also fortify wheat and maize flour with folic acid.

Taking a folic acid supplement before and during pregnancy can lower the chance of certain types of birth defects. Folic acid is available over the counter as a supplement and is also often found in prenatal vitamins.

How much folic acid should I be taking?

In general, it has been recommended to take 400 micrograms (mcg), or 0.4 milligrams (mg) of folic acid per day, whether pregnant or not. For people who are not already taking a daily folic acid supplement, and are planning a pregnancy, it has been recommended to start taking folic acid at least 1 month before a pregnancy.

During pregnancy, the recommended daily amount of folic acid is 600-800 mcg. Most people can get enough folic acid by eating foods with folate and by taking a folic acid supplement (as part of a prenatal vitamin or a separate supplement).

In addition to daily recommended amounts of vitamins, there are also tolerable upper intake levels, abbreviated as “UL”. The UL is the highest level of daily nutrient intake recommended for most people. The UL for folic acid / folate is 1,000 micrograms (mcg), or 1 milligram (mg) per day.

However, there are situations where people are recommended to take more than 1mg per day prior to and during pregnancy. This is most important for some people with a family history of a child with a neural tube birth defect (an opening in the spine or skull). Extra folic acid might also be recommended for people who take certain medications, drink large amounts of alcohol, or have diseases of the intestines and cannot absorb as much folic acid into their body. Talk with your healthcare provider about your medication and health conditions and ask if they might affect the amount of folic acid in your body. Your providers can go over 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 and at least one month before getting pregnant.

Does taking folic acid increase the chance for miscarriage?

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

Does taking folic acid increase the chance of birth defects?

Every pregnancy starts out with a 3-5% chance of having a birth defect. This is called the background risk. Taking folic acid before and during pregnancy lowers the chance of a baby having neural tube birth defects (an opening in the spine or skull). Taking folic acid might also lower the chance of other birth defects.

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

Taking folic acid at recommended levels is not expected to cause 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 chance of some pregnancy complications such as preterm delivery or getting high blood pressure during pregnancy, and reduce the chance of stillbirth or death in the newborn period.

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

Studies have not been done to see if folic acid can cause behavior or learning issues for the child.

Breastfeeding while taking folic acid:

Folic acid is naturally found in the breast milk of people who are well-nourished. While breastfeeding, it is recommended to get 500 mcg (0.5 mg) of folic acid every day. Babies get folic acid from breastmilk, so it is important to get enough folic acid while breastfeeding. Be sure to talk to your healthcare provider about all of your breastfeeding questions.

If a male takes folic acid, could it affect fertility (ability to get partner pregnant) or increase the chance of birth defects?

Some studies have suggested that folic acid is needed to make healthy sperm. In one study involving men with infertility folic acid supplementation increased sperm motility (how well the sperm can move). The recommended amount of folic acid for males is 400 mcg/day (0.4 mg/day). If there is a concern about how much folic acid a person is getting, talk with a healthcare provider. In general, exposures that fathers or sperm donors have are unlikely to increase the risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.

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