Congenital heart disease, or congenital heart defect, is a problem with your heart that is present when your child is born. So, the only way to protect your child is while you are pregnant. Scientists do strongly believe that smoking and drinking during pregnancy add to the risk for congenital heart disease. So, you should not smoke or drink while pregnant. This act in itself will not prevent congenital heart disease, per se, but it will lessen your risk.