Risk factors

It's not known why atrial septal defects occur, but some congenital heart defects appear to run in families and sometimes occur with other genetic problems, such as Down syndrome. If you have a heart defect, or you have a child with a heart defect, a genetic counselor can estimate the odds that future children will have one.

Some conditions that you have during pregnancy can increase your risk of having a baby with a heart defect, including:

• Rubella infection. Becoming infected with rubella (German measles) during the first few months of your pregnancy can increase the risk of fetal heart defects.
• Drug, tobacco or alcohol use, or exposure to certain substances. Use of certain medications, tobacco, alcohol or drugs, such as cocaine, during pregnancy can harm the developing fetus.
• Diabetes or lupus. Having diabetes or lupus might increase your risk of having a baby with a heart defect.