Congenital cytomegalovirus (CMV) infection refers to a condition where cytomegalovirus is transmitted in the prenatal period. CMV is a member of the virus family herpesviridae and is the most common intrauterine infection. Human cytomegalovirus is one of the vertically transmitted infections that lead to congenital abnormalities. Others include toxoplasmosis, rubella, herpes simplex, and syphilis. Presentation For infants who are infected by their mothers before birth, two potential adverse scenarios exist: Generalized infection may occur in the infant, and can cause complications such as low birth weight, microcephaly, seizures, petechial rash similar to the "blueberry muffin" rash of congenital rubella syndrome, and moderate hepatosplenomegaly (with jaundice). Though severe cases can be fatal, with supportive treatment most infants with CMV disease will survive. However, from 80% to 90% will have complications within the first few years of life that may include hearing loss, vision impairment, and varying degrees of learning disability. Another 5% to 10% of infants who are infected but without symptoms at birth will subsequently have varying degrees of hearing and mental or coordination problems. CMV is the most common cause of non-genetic sensorineural hearing loss in children. The onset of hearing loss can occur at any point during childhood, although commonly within the first decade. It is progressive and can affect both ears. The earlier the mother contracts the virus during pregnancy the more severe the effects are on the fetus, similarly the incidence of SNHL is dependent on which trimester of pregnancy CMV is contracted. The virus accounts for 20% of sensorineural hearing loss in children. These risks appear to be almost exclusively associated with women who previously have not been infected with CMV and who are having their first infection with the virus during pregnancy. There appears to be little risk of CMV-related complications for women who have been infected at least 6 months prior to conception. For this group, which makes up 50% to 80% of the women of child-bearing age, the rate of newborn CMV infection is 1%, and these infants appear to have no significant illness or abnormalities. The virus can also be transmitted to the infant at delivery from contact with genital secretions or later in infancy through breast milk. However, these infections usually result in little or no clinical illness in the infant. CMV can also be transferred through blood transfusions and close contact with large groups of children. To summarise, during