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The One Supplement Pregnant Women Should Take

TIME Health
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A government task force has reaffirmed its stance that women who are pregnant, or planning to become pregnant, should take folic acid supplements as a way to prevent birth defects.

On Tuesday, the U.S. Preventive Services Task Force, an independent panel of national medical experts, released its final recommendation on folic acid supplements for the prevention of birth defects. The group looked at 24 studies on the benefits and potential harms of folic acid supplementation and concluded that they're safe and effective. The task force regularly re-visits health issues in order to ensure that government guidelines for Americans are in line with the latest science.

Folic acid has repeatedly been shown to prevent improper brain and spinal chord development, called neural tube defects. Many birth defects happen in the first few weeks of pregnancy, which is why doctors recommend women start taking a daily supplement of 400 to 800 micrograms of folic acid.

The most important times for women to take the supplements are a month before becoming pregnant and throughout the first three months of pregnancy, the task force concludes.

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Dr. Alex Kemper, a member of the task force and professor of pediatrics at Duke University Medical School, says that given how safe folate supplementation is, women could take the pills for longer if they desired. "M ost [defects] seem to happen early in pregnancy, before a woman may even know she’s pregnant," he says. "Given that only half of pregnancies are planned, it makes sense for any woman who might become pregnant to be taking the supplements."

Women can get folate naturally from their diets, if they eat foods high in the nutrient, like dark green leafy vegetables, legumes and oranges. But around 75% of women do not get the recommended daily amount of folate from their diet alone, the new recommendation says.

"The recommendation is to make sure women get enough folic acid to prevent defects, and the one really sure way is by taking the supplement," says Kemper.

The Task Force has given the guideline an "A" recommendation, which means there is a high certainty of a substantial benefit.

Kemper says women who want to take daily folate supplementation can either get it through folate-specific pills or in a multi-vitamin, as long as it has the recommended 400 to 800 microgram dosage.

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