What is a congenital heart defect?
When the heart or blood vessels near the heart do not develop normally before birth, a condition called congenital heart defect occurs.
Congenital heart defects occur in about nine of every 1,000 infants. More than one million adults in the US experience congenital heart disease. Many young people with congenital heart defects are living into adulthood now.
In most cases, the cause is unknown. Sometimes a viral infection or hereditary condition causes the condition. Some congenital heart defects are the result of too much alcohol or drug use during pregnancy.
Most heart defects either cause an abnormal blood flow through the heart or obstruct blood flow in the heart or vessels.