Up to 1.3 million Americans alive today have some form of congenital heart defect. In the United States, about 36,000 children are born with a heart defect each year. At least nine of every 1,000 infants born each year have a heart defect. The causes of congenital heart disease are still under investigation, but there scientists and physicians are making progress.
Causes of Heart Defects
Unknown cause: We don't know the exact cause of most heart defects. Although the reason defects occur is presumed to be genetic, only a few genes have been discovered that have been linked to the presence of heart defects. So they're likely due to a combination of multiple genetic and environmental factors. There's usually a 2 to15 percent chance of a heart defect happening again in the family. The odds depend on what type of defect you have and whether anyone else in your family has a heart defect.
Genetic syndrome: Some people with congenital heart defects have a specific genetic condition that can include other health problems. They may or may not know that they have such a condition. The chance for their child to also have this condition can be as high as 50 percent. These conditions can vary widely in their severity, so children may have less serious or more serious health problems than their parents. Learn more about genetic counseling.
Single gene: Rarely, congenital heart defects are caused by changes in a single gene. Often when this is the case more than one person in the family has a heart defect. The chance for another family member to have a heart defect can be as high as 50 percent.
Environmental exposure: Heart defects can also be caused by something your mother was exposed to in her pregnancy with you, such as an infection or a drug. In this case, the chance that your children will have heart defects is no higher than that of the average person.
Taking part in research
As an adult with congenital heart defects, you may be able to help improve our understanding by taking part in research. There's still a lot that we don't know about why heart defects happen. It's possible that future research will discover these causes. Participating in research could help your family and other families better understand their heart defect and the chance it will occur again in the family. Ask your genetic counselor about research studies you could take part in.