Figure 1.

Frequency of maternal report of prenatal congenital heart defect diagnosis by defect type, for simple, isolated defects^a, National Birth Defects Prevention Study, 1998–2005 (n=4,455)

Note: Error bars represent exact 95% confidence intervals

^a A case was categorized as having a “simple” heart defect if s/he had one heart defect or a well-defined constellation of defects such as hypoplastic left heart syndrome or tetralogy of Fallot and “isolated” if no extracardiac defects were present. For presentation purposes, we only present the frequencies for CHD types with ≥ 50 simple, isolated cases across all study sites.