Introduction “Screening” in the field of pediatric cardiology is currently implemented in many different areas The interest and opportunities for screening have increased and evolved along with the increase in our knowledge base Screening currently includes in utero screening for congenital heart disease (CHD), pulse oximetry after birth screening for CHD, screening for at-risk entities for sudden cardiac death, screening for neurodevelopmental issues, screening for familial forms of CHD, and screening for other familial, genetic, and preventive issues such as the hyperlipidemias, as well as environmental issues such as hypertension and metabolic disorders This chapter reviews these complex issues and suggests potential future endeavors in these areas Fetal Echocardiographic Screening (see also Chapters 7 and 8) Malformations of the cardiovascular system are some of the most common birth defects The incidence of CHD in the live-born population is estimated at slightly less than 1%.1 However, the incidence of CHD in the fetus may be significantly higher, as cardiac defects are estimated to be much more frequent in stillborn infants.2,3 Detecting a cardiac defect, if present, in the fetus is dependent on the timing of the examination, the training and experience of the ultrasonographer and interpreting physician, and the equipment use.4–6 At minimum, two-dimensional, color and spectral Doppler should be used As the echocardiographic appearance of some congenital heart defects can change throughout gestation, one exam at one time point may not be sufficient Accurate and sensitive fetal diagnosis is important as the prenatal diagnosis of CHD can affect not only the family's desire to continue with the pregnancy but can allow for planning delivery at or near a cardiac surgical center, psychological preparation of the family prior to delivery, as well as surgical planning.7 Over recent years, criteria for fetal echocardiographic screening of fetuses at higher risk of CHD have been established (Table 89.1).8 For these higher-risk pregnancies, a thorough fetal echocardiogram should be performed in the second trimester Table 89.1 Indications for Fetal Echocardiography Indication for Fetal Echocardiography MATERNAL/FAMILIAL INDICATIONS Maternal pregestational diabetes mellitus (diabetes mellitus diagnosed in the first trimester) Maternal phenylketonuria Maternal autoantibodies (SSA/SSB+) Maternal medications Angiotensin-converting enzyme inhibitors Retinoic acid Nonsteroidal antiinflammatory drugs Anticonvulsants Risk of Congenital Heart Disease (%) 3%–5% 12%–14% 1%–5% (increased to 11%–19% if prior child affected with congenital heart block or neonatal lupus) 2.9% 8%–20% 1%–2% structural CHD, 5%–50% ductal constriction 1.8% Lithium Vitamin A Paroxetine Maternal rubella infection Maternal infection with suspicion of fetal myocarditis Assisted reproduction technology CHD in first-degree relative of fetus First- or second-degree relative with disorder with mendelian inheritance with CHD association CHD in second-degree relative of fetus (less risk, may be indicated) FETAL INDICATIONS Cardiac abnormality suspected on obstetrical ultrasound Extracardiac abnormality suspected on obstetrical ultrasound Fetal karyotype abnormality Fetal tachycardia or bradycardia Frequent or persistent irregular heart rhythm Fetal increased nuchal translucency (≥3 mm) Monochorionic twinning Fetal hydrops or effusions