Key Findings: Factors associated with Dandy-Walker Malformation (DWM), a rare birth defect of the brain

In a new study published in the American Journal of Medical Genetics, Part A, researchers looked at specific factors that might increase the risk for having a baby with Dandy-Walker malformation (DWM), a rare birth defect that affects the back part of the brain. Researchers looked at many different environmental and lifestyle factors (such as the mother’s and father’s race, mother’s education and age, and certain exposures before and during pregnancy, such as smoking, alcohol use, and infections) and found that most of them were not related to having a baby with DWM. The researchers did identify a few factors that were more common among babies with DWM than among babies without DWM, including black race mothers, twinning, or a history of infertility treatment. The lack of environmental factors suggests that genetic factors might play an important role in DWM. More study of these factors might provide additional clues to the causes of DWM. You can read an abstract of the article here.

Main Findings

• Researchers found that the following  factors were more common among babies with DWM:
  • Mothers that are of black race
  • Twinning
  • History of infertility treatment
• Future studies should further examine the roles of race, twinning, infertility treatment, and genetics in the development of DWM.

About this Study

• Researchers used data on babies that were due to be born between October 1, 1997 and December 31, 2009 from the National Birth Defects Prevention Study (NBDPS).  The NBDPS is a population-based, multi-site study, which aims to understand factors related to the risk for major birth defects. Population-based means that researchers look at all babies with birth defects who live in a defined study area, which is important to get a complete picture of what is happening within this known population.
• For this study, researchers looked at factors from one month before pregnancy through the third month of pregnancy.
• Birth defects were identified through birth defects tracking systems in Arkansas, California, Georgia, Iowa, Massachusetts, New Jersey, New York, North Carolina, Texas, and Utah.

CDC’s Activities: Birth Defects

CDC is working to address birth defects with the following activities:

• Tracking: CDC tracks birth defects through several state tracking systems and regional programs. CDC also supports and collaborates with the National Birth Defects Prevention Network (NBDPN).

• Research: CDC funds the Centers for Birth Defects Research and Prevention, which collaborate on large studies such as the National Birth Defects Prevention Study (births 1997-2011) and the Birth Defects Study To Evaluate Pregnancy exposureS (BD-STEPS) (began in 2014). These studies work to identify factors related to the risk for birth defects.

More Information

For more information about birth defects, please visit www.cdc.gov/birthdefects.

Key Findings Reference

Reeder MR, Botto LD, Keppler-Noreuil KM, Carey JC, Byrne JLB, Feldkamp ML. Risk Factors for Dandy-Walker Malformation: a Population-based Assessment. Am J Med Genet A. 2015 May 1. [Epub ahead of print].