What you need to know:
Folic acid, a B vitamin, helps prevent birth defects of the brain and spinal cord when taken before the end of early pregnancy. It is available in most multivitamins, as a folic acid-only supplement and in some foods.
What you can do:
Take a multivitamin with 400 micrograms of folic acid every day before pregnancy and during early pregnancy, as part of a healthy diet.
Eat a healthy diet that includes foods that contain folate, the natural form of the vitamin. Such foods include fortified breakfast cereals, dried beans, leafy green vegetables and orange juice.
If you have already had a pregnancy affected by a birth defect of the brain or spinal cord, ask your health care provider how much folic acid you need. Studies have shown that taking a larger dose of folic acid daily can reduce the risk of having another affected pregnancy. The larger dose needs to be taken at least 1 month before pregnancy and in the first trimester of pregnancy. The recommended dose in this case is 4 milligrams (4,000 micrograms).
Take Folic Acid Before You're Pregnant
Folic acid is a naturally occurring B vitamin. It helps a fetus's neural tube develop properly. The neural tube is the part of a developing baby that becomes the brain and spinal cord. Folic acid must be taken before and during early pregnancy when the neural tube is developing.
The best way to get enough folic acid is to take a multivitamin with 400 micrograms of folic acid in it and eat a healthy diet. Most multivitamins have this amount, but check the label to be sure. You also can get folic acid in your diet, but it's hard to get enough every day through food alone. That's why the March of Dimes encourages all women of childbearing age to take a multivitamin containing folic acid every day as part of a healthy diet.
Folic acid works, but it only works if taken before and during the first few weeks of pregnancy, when the neural tube is developing into the brain and spinal cord. When the neural tube does not close properly, a baby is born with a very serious birth defect called a neural tube defect (NTD). About 3,000 pregnancies are affected by NTDs each year in the United States. If all women took adequate folic acid before conception and during early pregnancy, up to 70 percent of NTDs could be prevented.
Once you're pregnant, you should increase your folic acid intake to at least 600 micrograms of folic acid. Your prenatal vitamin should have the right amount of folic acid you'll need during pregnancy.
Folic acid has no known toxic level. If you ate a bowl of fully fortified cereal (400 micrograms), took a folic acid supplement (400 micrograms), and ate fortified foods and foods rich in folate, you would not get too much folic acid. Still, the U.S. Centers for Disease Control and Prevention recommends that women consume no more than 1,000 micrograms of synthetic folic acid a day.