Cytomegalovirus infection.

Cytomegalovirus (CMV) infection is the most common perinatal infection and may result in severe injury to the fetus. Forty percent to 50% of infants delivered to mothers with primary CMV will have congenital infections. Of these, 5% to 18% will be overtly symptomatic at birth. The mortality rate in these children is almost 30%; approximately 80% of the survivors have severe neurological morbidity. The majority of congenitally infected infants will be asymptomatic at birth; 10% to 15% of these children subsequently have sequelae such as visual and auditory defects. If recurrent or reactivated CMV infection develops during pregnancy, the risk of serious fetal injury is very low. Similarly, neonatal infection acquired during delivery or from breast feeding also poses minimal risk to the child. Because antimicrobial therapy and immunoprophylaxis for CMV infection are unsatisfactory, pregnant women must be educated about preventive measures.