Why is folic acid important during pregnancy?

Diana Meeks
Diana Meeks on behalf of Sigma Nursing
Family Practitioner

Folic acid has two import functions during pregnancy. First, folic acid helps the body produce the extra blood volume the body needs during pregnancy. Secondly, folic acid plays a role in the prevention of neural tube defects, specifically spina bifida and anencephaly, in the developing embryo/fetus.

Dr. Frederick Friedman, MD
OBGYN (Obstetrician & Gynecologist)

Folic acid is one of the B-complex vitamins. Daily intake of at least 400micrgrams (the amount of folic acid found in many over the counter vitamins) has been shown to significantly reduce the risk of neural tube defects—defects in the closure of the brain and/or spinal cord coverings. Recent data have suggested that it might also lower the risk of other birth defects as well.

Folic acid is also important in cell turnover and division, so it is critical to have sufficient intake throughout pregnancy and in the non-pregnant state.

Folic acid is a B vitamin that our bodies use to make new cells. Everyone needs folic acid, but for women who can get pregnant, it is extremely important. If a woman has enough folic acid in her body before she is pregnant, it can help prevent major birth defects of her baby's brain and spine, called neural tube defects or NTDs. Women need to take folic acid every day, starting before they are pregnant to help prevent NTDs. The Centers for Disease Control and Prevention (CDC) and the US Public Health Service urge every woman who could become pregnant to get 400 micrograms (mcg) of synthetic folic acid every day.

For women who are already pregnant, it is important to continue to take folic acid every day. Folic acid is needed to help the fetus grow and develop.

Folate (its name when occurring naturally) or folic acid (its name in supplements) is part of the B-complex family of vitamins. Folic acid is often prescribed for pregnant women, because it is essential for the normal development of the brain and spinal cord of the fetus. Thus, we tend to think of folate as being essential while we are in utero.

Joan Salge Blake, MS, RD
Nutrition & Dietetics Specialist

Folate is vital to making the DNA in your cells. If the synthesis of DNA is disrupted, your body’s ability to create and maintain new cells is impaired. For this reason, folate plays an important role in preventing certain birth defects.

Folate is needed to create new cells so that the baby can grow and develop. For this reason, folate plays an extremely important role during pregnancy, particularly in the first few weeks after conception, often before the mother knows she is pregnant.

A deficiency during pregnancy can result in birth defects called neural tube defects. The neural tube forms the baby’s spine, brain, and skull. If the neural tube doesn’t develop properly, two common birth defects, anencephaly and spina bifida, can occur. In anencephaly, the brain doesn’t completely form so the baby can’t move, hear, think, or function. An infant with anencephaly dies soon after birth.

In spina bifida, the baby’s spinal cord and backbone aren’t properly developed, causing learning and physical disabilities, such as the inability to walk. Folic acid reduces the risk of these birth defects by 50 to 70 percent if consumed at least the month prior to conception and during the early part of pregnancy.

Research studies to date suggest that synthetic folic acid has a stronger protective effect than the folate found naturally in foods. Because 50 percent of pregnancies in the United States are unplanned, women at risk of becoming pregnant should consume 400 micrograms of synthetic folic acid daily from fortified foods or supplements, along with a diet high in naturally occurring folate.

Women with a family history of neural tube defects should, under the guidance of their physicians, take even larger amounts.

Boston Women's Health Book Collective
Administration Specialist

Folate is an essential vitamin that your baby needs in order to grow. Consuming enough folate at the very beginning of pregnancy can prevent 50 to 70 percent of neural tube defects, which cause birth impairments such as spin bifida.

Folate, which is a B vitamin, is sometimes called the "foliage" vitamin, because it is found in most dark green, leafy vegetables. Folate is also found in foods such as dried peas, beans, and lentils; liver; and beef. In addition, many ready-to-eat breakfast cereals, breads, and pastas are fortified with folic acid, the synthetic form of folate.

Many women do not get enough folate from the food we eat. Therefore, it is generally recommended that women who plan on becoming pregnant begin taking 400 micrograms of folic acid several months before trying to conceive and continue taking it through the first three months of pregnancy. Most prenatal vitamins include the full amount of folic acid needed per day during pregnancy. If you are taking medication for a seizure disorder or if you have a family history of, or have had a previous pregnancy affected by, a neural-tube defect, it is recommended that you take 4 milligrams of folic acid.

Our Bodies, Ourselves: Pregnancy and Birth

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Our Bodies, Ourselves: Pregnancy and Birth

Stacy Wiegman, PharmD
Pharmacy Specialist

Folic acid is important during pregnancy because it helps protect against birth defects. The B vitamin is important for the proper development of a fetus's neural tube, which forms the brain and spinal cord. If a pregnant woman doesn't get enough folic acid, it can put her baby at risk of a birth defect such as spina bifida.

For that reason, experts recommend that women of childbearing age get 400 to 800 micrograms (mcg) of folic acid a day. Women who are breast-feeding need 500 mcg. A woman who has had a baby with a spinal defect or has a family member whose baby has had one may need a prescription for 4,000 mcg folic acid.

"All nutrients are essential in preparing for pregnancy, but one—folate or folic acid—merits special consideration.

Soon after conception, folate helps develop the baby's neural tube, which becomes the spinal cord and brain. Women who consume enough folate, particularly in the weeks prior to conception and during the first three months of pregnancy, may reduce the risks of neural tube defects.

Women of childbearing age should consume 400 micrograms of folic acid from fortified foods in grains, such as breads, cereals or pastas, vitamin supplements or both, in addition to the folate found naturally in other foods."

Dr. Diana K. Blythe, MD
Folic acid is important in pregnancy because it helps with the developing nervous system of the fetus. Most pregnant women should get at least 1mg of folic acid daily. However, women who have had a pregnancy in the past which had neural tube defects should take at least 4mg of folic acid daily during pregnancy. 

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.