Studies show that the risk of Spina Bifida and other NTDs may be influenced by the mother’s diet, especially the amount of the B vitamin folic acid she consumes. In 1992, the U.S. Public Health Service recommended that women of childbearing age (15-44) who are capable of becoming pregnant should consume 400 micrograms of folic acid every day. This amount of folic acid has been shown to reduce the risk of Spina Bifida or other NTDs by 50 to 70 percent.
Women should begin taking folic acid at least one month before conception through the first month of pregnancy, when NTDs occur. Because many pregnancies are unplanned, all women who might become pregnant should consume the recommended amount of folic acid daily.
It is recommended that women eat a healthy diet, including foods rich in folic acid, and take a multivitamin every day. This is the only sure way to get all the folic acid and other vitamins and minerals a woman needs. Foods that contain natural folic acid include orange juice, green leafy vegetables and beans. Fortified breakfast cereals, enriched grain products (including flour, breads, pasta, cornmeal and rice), and vitamins contain a synthetic form of folic acid. It is more easily absorbed by the body than the natural form. Women should not take more than 1,000 micrograms of synthetic folic acid unless a health care provider recommends it.
A 1991 British study reported that supplementation with higher doses (4 milligrams) of folic acid before conception and through the first three months of pregnancy reduced by 70 percent the risk of NTDs in babies born to women who had already had affected babies. Based on this and other studies, the U.S. Centers for Disease Control and Prevention (CDC) recommends that any woman who has had a baby with an NTD consult her health care provider before attempting to conceive again, so that she can begin to take 4 milligrams of folic acid when she plans to become pregnant and continue through the first three months of pregnancy.