Approximately 35,000 babies are born with a defect each year. Most of the time we do not know. 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. Rarely the ingestion of some drugs and the occurrence of some infections during pregnancy can cause defects. Severe heart disease generally becomes evident during the first few months after birth.
Some babies are blue or have very low blood pressure shortly after birth.
Other defects cause breathing difficulties, feeding problems, or poor weight gain. Minor defects are most often diagnosed on a routine medical check up. Minor defects rarely cause symptoms. While most heart murmurs in children are normal, some may be due to defects. Congenital heart defects are the most common birth defect and are the number one cause of death from birth defects during the first year of life.