Please read chapter 12 and provide the summary Congenital defects are a major cause of death and disability in infants and children. Approximately 3% of all newborns have a major abnormality apparent at birth.1 Other problems show up later, with as many as 7.5% of children being diagnosed with a congenital defect in their first five years.2 Such abnormalities may be inherited in the child’s genes, or they may be caused by birth injury or by the mother’s exposure to an infectious agent or toxic substance during pregnancy. Genes also play a role in many diseases of later life. Because the birth of healthy children has traditionally been a high priority for public health, education and prenatal care for pregnant women have been encouraged. As more has been learned about how certain infectious agents, drugs, and chemicals can cause birth defects, greater public health efforts have been directed toward preventing women’s exposure to these substances. Until the past few decades, little could be done to prevent genetic abnormalities. Now, however, technological developments have opened up vast possibilities in the detection of defective genes. These discoveries have had many clear benefits, but they have also raised many difficult ethical questions.
