If my first child was born with chd what are the chances my second will have a heart defect too?

Depends on the type: Heart defects are common and if one child has a congenital heart defect there is an increased risk in future siblings. However, only 2-3% of congenital heart defects are related to a family history. The absolute chance of having a recurrence depends on the exact type of defect. Some conditions recur frequently while others recur rarely. Speak to a cardiologist for more details.

Depends on defect: The exact chances differ with different kinds of heart disease, and any comorbidities, such as hereditary disorders, but generally the chances are somewhat higher than the general population.

Other defects?: I agree with dr. Onyeije's note! additionally, i would be interested in knowing if that first infant had other birth defects or any identifiable syndrome by genetics - that would greatly affect recurrence risk calculations. Multifactorial inheritance means that 2-5% of future babies will be affected. You can decrease that risk significantly (75%?) by taking Folic Acid before all future conceptions.

Depends: Some defects such as transposition there is no increased risk. Other defects have an increased risk ranging from 2-8%. Ask your pediatric cardiologist for a specific answer.

~3-5%: When a person has chd, or has a child with chd, their future offspring have a slightly higher risk of having chd as well (i'm sure you know this). The quoted numbers differ, but most people agree that the risk is ~3-5% of having any form of chd.