Research

Why We Do Research

Birth defects can cause lifelong problems with health, growth, and learning. We want to find ways to prevent birth defects. To do that, we need to know what causes them. Research gives us important clues about things that might raise or lower the risk of having a baby with a birth defect. Those clues help us develop sound public health policies for prevention.

Research has shown that taking folic acid before getting pregnant and in early pregnancy lowers the risk of having a baby with certain birth defects. This research finding led to the advice that all women who can get pregnant should take 400 micrograms of folic acid daily. In order to learn more, CDC continues to conduct folic acid research.

Current Folic Acid Research

National Birth Defects Prevention Study

The National Birth Defects Prevention Study is the largest population-based U.S. study looking at potential risk factors and causes of birth defects. Current folic acid research activities include:

• Looking at how a woman’s intake of micronutrients, including folic acid, may affect the risk for specific birth defects.
• Studying why Hispanics appear to be at higher risk for neural tube defects.
• Learning about women’s behaviors related to preventing birth defects, including folic acid use and alcohol use.

U.S.-China Collaborative Project

For more than 20 years, CDC and the Peking University Health Science Center (PUHSC) have collaborated on birth defects research. In the mid 1990’s, CDC and PUHSC began evaluating a large-scale community intervention program in China.

In this program, they tested whether giving women 400 micrograms of folic acid before and during early pregnancy prevents neural tube defects (NTDs). Among the babies of women who took the daily recommended amount of folic acid, the risk of having an NTD dropped 85% in high-prevalence areas and 41% in areas with prevalence similar to the United States. In addition, research from this community intervention program showed that folic acid use before and during early pregnancy did not increase a woman’s risk for miscarriage or multiple births.

The CDC has used the China collaboration to explore topics such as folic acid and infant death rates, congenital heart defects, changes in blood level of folic acid with different folic acid doses, and long-term evaluation of the women and children from the community intervention program.

National Health and Nutrition Examination Survey

The National Health and Nutrition Examination Survey (NHANES) is a program of studies designed to evaluate the health and nutritional status of adults and children in the United States. The survey is unique in that it combines interviews and physical examinations. The CDC uses information from this study to look at the population’s folic acid intake as well as blood levels of folate and other micronutrients.