Very low birth weight infants born to cytomegalovirus-seropositive mothers fed with their mother's milk: a prospective study.

To assess the risk of post-natal cytomegalovirus (CMV) transmission to very low birth weight (VLBW) infants fed with their mother's fresh milk. Prospective, observational study of 80 VLBW infants and their 68 mothers. Infants' urine and their own mother's fresh breast milk were tested for CMV by means of culture tests once a week until discharge. CMV in infected milk and urine were genotyped. The clinical course, laboratory findings, and outcome of infants infected with CMV at 2 years of age are reported. Fifty-three mothers (78%) were CMV-seropositive at delivery. CMV was detected in the milk of 21 of 53 seropositive mothers (40%), and CMV was in the urine in 9 of 26 infants (35%) fed with CMV-positive milk. The same gN-genotype was found in milk and urine. Three infected infants <28 weeks gestational age (GA) had a mild sepsis-like illness. Five more infants had neutropenia, conjugated hyperbilirubinaemia, or both. Post-natal CMV infection occurred in 1 of 19 infants with a GA<28 weeks who were treated at birth with intravenous immunoglobulin versus 3 of 5 non-treated infants (P < .02). Symptomatic CMV infection was associated with bronchopulmonary dysplasia. No neurosensorial sequelae were found at 2 years of corrected age. CMV infection via fresh human milk is mild, self-limiting, and without sequelae. Very-low GA and pre-existing chronic diseases are associated with symptomatic infection.