Congenital infectious diseases, transmitted during the course of pregnancy, are estimated to affect nearly one in every hundred births worldwide. These infections may be associated with fetal and infant adverse health outcomes, due to congenital malformations caused by in utero transmission of the infectious organism itself (as is the case with cytomegalovirus, toxoplasmosis, syphilis and Zika virus), or due to chronic infection in the infant (as is the case with human immunodeficiency virus [HIV] and hepatitis B and C). In addition, children who are exposed, yet uninfected, may still suffer from the consequences of exposure to infectious pathogens or to the drugs given to treat pregnant women and prevent in utero transmission (as may be the case with HIV infection).