Metropolitan Atlanta Congenital Defects Program

Birth defects affect approximately 120,000 newborns each year in the United States—one in every 33 babies. While the medical community has made advances in preventing and treating these conditions, in many cases the causes remain unknown.

The National Center on Birth Defects and Developmental Disabilities (NCBDDD), which is part of the Centers for Disease Control and Prevention, started the Metropolitan Atlanta Congenital Defects Program (MACDP) in 1967. This program was the first population-based study of birth defects, and also an early foray for CDC into surveillance of noninfectious diseases. Its goal is to gather comprehensive data on the prevalence of birth defects among a representative population, shedding light on the causes and leading to better services for individuals and their caregivers who are directly affected.

The program includes both surveillance—tracking the occurrence of birth defects—and research studies that collect data to contribute to risk factor assessment, prevention measures, and interventions. It also serves as a training opportunity for public health researchers, a source of information for policymakers, and a model for similar tracking programs around the world.

Maintaining Scientific Rigor under Logistical Constraints


Since 2008, RTI has provided a wide range of epidemiological support services to MACDP.  Our experts provide scientific support to all aspects of the program. We use medical records to estimate the prevalence of birth defects in both live and stillborn children whose mothers gave birth in the Metro Atlanta area.

In recent years, MACDP has faced challenges associated with the expansion, urbanization, and increased racial diversity of Atlanta. And in 2012, funding cuts restricted the study to three counties—DeKalb, Fulton, and Gwinnett—down from its original five. In response to these challenges, we have applied methodological expertise to extract the same quality data from fewer counties, saving on costs while still yielding reliable and useful results.

Our abstractors, the people who conduct active surveillance for birth defects, visit multiple medical records facilities, collecting clinical information and relevant demographic data. Faced with decreased funding and staffing levels, our experienced team increased their productivity by 70 percent during our first five-year contract. They also adapted their processes to accommodate the advent of electronic medical records, which have grown increasingly commonplace.

Our team includes doctoral-level geneticists, epidemiologists, nurses, and others with specialized expertise on the varied origins and consequences of birth defects. This medical and scientific knowledge base complements our expertise in records abstraction, enabling RTI to provide the full spectrum of support needed by our client.

Gaining Insights to Inform Recommendations for Healthy Pregnancies and Births


The data we gather on the prevalence of congenital defects is an invaluable resource for researchers looking to understand major congenital health issues, including heart defects, spina bifida, and Down syndrome. Recent findings based on project data have identified behavioral and environmental influences on the risk of birth defects, including

  • The rate of neural tube defects, such as spina bifida, decreased with programs to increase mothers’ intake of folic acid.

  • Women who were obese before becoming pregnant had a higher risk of certain birth defects.

  • Congenital heart disease is associated with chromosomal abnormalities, maternal age, and noncardiac major structural anomalies, but not with ambient air pollution.


These and other results translate directly into useful recommendations for the prevention and treatment of birth defects. Drawing on MACDP data, NCBDDD develops information and resources for pregnant women, health care providers, families of people with birth defects, and the general public.

As we continue our support for MACDP, our experts are committed to delivering the expertise, experience, and flexibility needed to ensure high-quality data that will inform and improve health outcomes.