Birth defects affect about 3% of all births in the United States, and the causes of two-thirds of birth defects remain unknown. In the past, it has been difficult to conduct a study large enough to examine specific risk factors for birth defects. BD-STEPS is an ongoing project that aims to advance research on major structural birth defects and stillbirth prevention strategies. The focus is on studying exposures during pregnancy that are related to chronic diseases and their treatments, infectious diseases, and medications.

BD-STEPS is a collaborative effort between the CDC’s National Center on Birth Defects and Developmental Disabilities (NCBDDD) and 7 centers throughout the United States, with the goal of collecting high-quality data to further knowledge surrounding birth defects and prevention strategies. BD-STEPS began interviewing women who had babies born beginning in January 2014.

Since BD-STEPS is a case-control study, women whose pregnancies were unaffected by a birth defect are also being recruited and asked to participate. Participation for this comparison group is designed as a random sampling, and selected individuals are contacted to ask if they’re interested in participating. These random samples include around 100 births for each year that the project is ongoing.

Both women whose pregnancies were affected by a birth defect and women whose pregnancies were unaffected are interviewed surrounding their experiences during pregnancy. They are asked questions about their family, health, and lifestyle. Since the cause of most birth defects is unknown, the interview questions cover a wide range of topics, with the intent of studying the answers from thousands of mothers in hopes of learning something new about the causes of birth defects.

BD-STEPS data is not released to the public, and no information is given to anyone who is not an approved children’s health researcher on this study. The privacy of the women and their families is safeguarded so that no identifiable information is available to researchers.