Following Standard Precautions (i.e., consider all body fluids except sweat potentially infectious, and use personal protective equipment when exposure to blood or body fluids is anticipated), as recommended by the Centers for Disease Control and Prevention for all healthcare personnel, will protect pregnant healthcare personnel against most infectious agents to which they may be exposed. However, because some infectious agents can cause congenital syndromes in the fetus when primary infection is acquired during pregnancy, there are additional concerns in pregnant or potentially pregnant healthcare personnel. For practical purposes, immunologic function is normal during pregnancy, and an otherwise healthy woman is not considered to be an immunocompromised host. Pregnancy does not increase the risk of acquisition of infections and, for most infectious agents, clinical manifestations of infections are no more severe in pregnant women than in those who are not pregnant. In view of the routes of transmission and ubiquity of some infectious agents (e.g., cytomegalovirus), restricting pregnant women from caring for patients with potentially transmissible infections is considered only for patients infected with parvovirus B19 and for patients with respiratory syncytial virus infections who are receiving ribavirin aerosol. Because patients with vaccine-preventable diseases should be cared for by only immune healthcare personnel, it is especially important for women contemplating pregnancy to obtain the needed vaccines before conception. Similar to nonpregnant healthcare personnel, susceptible pregnant healthcare personnel should be restricted from contact with patients with rubeola, rubella, varicella, and smallpox. Much anxiety among pregnant healthcare personnel results from misinformation concerning epidemiology and transmission of infectious agents. The emphasis must be on education of all healthcare personnel of childbearing age, ideally before pregnancy, or at least as soon as pregnancy is diagnosed. It is important to note that the incidence of cytomegalovirus and parvovirus infection is not increased among healthcare personnel compared with other occupations, especially day care center staff and school teachers.