Risk factors

By Mayo Clinic Staff

It's not known why atrial septal defects occur, but 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 any future children will have one.

Some conditions that you have or that occur during pregnancy may 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. If you have diabetes or lupus, you may be more likely to have a baby with a heart defect.
  • Obesity. Being extremely overweight (obese) may play a role in increasing the risk of having a baby with a birth defect.
  • Phenylketonuria (PKU). If you have PKU and aren't following your PKU meal plan, you may be more likely to have a baby with a heart defect.
March 07, 2017