Risk factors

Things that might increase a baby's risk of developing atrioventricular canal defect include:

• Down syndrome in the baby
• German measles (rubella) or another viral illness in the mother during early pregnancy
• Poorly controlled diabetes during pregnancy
• Drinking alcohol during pregnancy
• Smoking during pregnancy
• Certain medications taken during pregnancy — talk to your doctor before taking any drugs while you're pregnant or trying to become pregnant
• Having a parent who had a congenital heart defect