On Sept. 11, 1992, the U.S. Centers for Disease Control and Prevention (CDC) began recommendations for folic acid supplements for prevention of fetal neural tube deficits in pregnancy. This change was enacted by the U.S. Congress, as part of the Preventive Health Amendments of 1992, to recognize CDC’s leadership role in the prevention of disease, injury, and disability.

Each year in the United States about 2,500 infants are born with the neural tube defects (NTDs) spina bifida and anencephaly. The evidence that consumption of folic acid, one of the B vitamins, before conception and during early pregnancy (the periconceptional period) can reduce the number of NTDs has been accumulating for several years.