Perinatal or early-postnatal cytomegalovirus infection in preterm infants under 34 weeks gestation born to CMV-seropositive mothers within a high-seroprevalence population.

In a prospective study, we evaluated the frequency, correlates, and clinical significance of perinatal or early-postnatal cytomegalovirus (CMV) infection in <34-week-gestation infants (n=95) born to CMV-seropositive mothers. None had congenital CMV infection. Overall, 21 (22.1%; 95% CI=14.2-31.8) infants were found to be infected; 10 excreted CMV at <60 days, and 11 had later excretion. Blood transfusion, birth weight, and vaginal delivery were not associated factors. Receiving natural breast milk within the first 30 days (OR=4.5, P=.02) or for >30 days (OR=7.9, P <.01) was associated with infection. Only one (4.8%) of the infected infants was symptomatic. For <34-week-gestation infants, frequency of perinatal and early-postnatal CMV infection is high. Early or prolonged exposure to breast milk is an associated factor. However, most infections are asymptomatic, indicating that CMV infection in preterm infants within such a population is a serious problem infrequently.