Which infections to screen for during pregnancy depends on whether they fulfill the prerequisites for screening. This is the case for rubella and chickenpox, for instance. Ideally, vaccination status should be checked prior to conception; otherwise, it must be checked in early pregnancy in order to be able to vaccinate the mother postpartum. Although syphilis is rare, it is a serious problem if it occurs in early pregnancy, and there is an effective treatment. HIV (human immunodeficiency virus) screening in pregnancy is well established. Group B streptococcus is the leading cause of neonatal sepsis, making screening advisable. Other infectious diseases, such as toxoplasmosis and primary cytomegalovirus infection, do not meet the criteria for systematic screening during pregnancy.