Congenital fetal infections

Neurodevelopmental Disabilities

The topic of this chapter is neurodevelopmental disabilities, with discussion focused on three prototypic neurodevelopmental disorders: mental retardation, autism, and cerebral palsy. These disorders are highlighted because the epidemiologic knowledge is more advanced; however, many of the important methodologic issues apply to other neurodevelopmental disorders. The chapter discusses the particular research challenges in achieving complete case ascertainment due to the problems of case finding and case confirmation. It presents information about the prevalence of each of these disorders and temporal changes in frequency over time, as well as the possible factors contributing to increased recognition of these disorders. The chapter summarizes investigations of risk factors for each disorder, including genetic factors and possible environmental etiologies.

1: Infections in pregnant women

Some infections are more serious in pregnant than non-pregnant women because of the potential for vertical transmission to the fetus or infant (eg, varicella, rubella, cytomegalovirus infection, toxoplasmosis and listeriosis). Pre-pregnancy or routine antenatal screening for presence of, or susceptibility to, some of these infections and appropriate management can prevent adverse fetal or perinatal outcomes; screening should include rubella IgG, hepatitis B surface antigen, serological tests for syphilis and HIV antibody. If certain other vertically transmissible infections are suspected because of a positive antenatal test result, confirmatory tests for maternal and, if indicated, fetal infection are essential before intervention is considered (eg, cytomegalovirus infection). For some vertically transmissible infections that are not readily preventable, appropriate management of maternal infection can reduce fetal damage (eg, toxoplasmosis).