• Outcome of pregnancy is known at the time of initial report. Types of known outcomes include prenatal testing reports in which the results are abnormal or outside the reference range, indicating possible abnormality in the fetus. Pregnancies in which prenatal testing indicates a normal pregnancy would also be excluded because inclusion of such pregnancies could potentially bias results toward a lower overall estimate of risk for defects. Typically pregnancies > 16 weeks gestation will have undergone prenatal testing that can identify whether a child has congenital abnormalities.