What Happens

Congenital heart defects happen when the heart doesn't form normally as the developing baby (fetus) grows in the uterus. Heart defects may cause problems with blood flow through the heart after a baby is born. The problems can affect the baby's blood and oxygen supply.

There are many types of congenital heart defects. If the defect lowers the amount of oxygen in the body, it is called cyanotic. If the defect doesn't affect oxygen in the body, it is called acyanotic. Some defects require treatment right away. Other defects get better on their own and don't require treatment.

Congenital heart defects happen in about 8 out of 1,000 babies born in the United States.¹ But only about one-third of these babies have major defects that need surgery or have defects that may cause death during the first year of life.¹ The number of congenital heart defects among premature babies is higher—about 2 out of 100 births.²

Congenital heart defects affect a similar number of boys and girls. But the types of defects that are common in boys and girls tend to differ.²

Not all defects are found when a child is very young. Some defects don't cause symptoms and aren't life-threatening. These defects may not be found until the teen years or later.

Long-term problems

Although many children and adults with corrected heart defects lead normal lives, heart defects can be related to or cause long-term risks that may include:

• Developmental delays or disabilities or behavior problems.
• Certain physical traits, such as smaller-than-average adult height and weight, clubbing, or cyanosis (bluish tint to the skin from low blood-oxygen levels). These can present challenges to a person's self-esteem and confidence.
• A shorter life span than average, if the defect is severe or if heart failure or other complications happen.

Adults

If you are an adult with a congenital heart defect, see the topic Congenital Heart Defects in Adults.

You may have to make decisions about:

• Pregnancy.
• Birth control.
• Type of employment.
• Health insurance.