Cytomegalovirus (CMV)
Maternal/Parental Infections Cytomegalovirus (CMV)

Cytomegalovirus (CMV)

Cytomegalovirus is considered a ubiquitous infection among humans. In the USA approximately 40-60% of birthing parents/mothers are CMV-seropositive, which means that they carry the virus. CMV is spread through bodily fluids, including breastmilk. Perinatal transmission can occur during pregnancy and labor & delivery as well as through breastmilk. Approximately 27% of CMV-seropositive lactating parents shed the CMV virus in their breastmilk. Term healthy newborn infants are at minimal risk for significant illness from CMV exposure,1 whereas very premature infants born before 30 weeks have a higher risk of significant illness from CMV infection.1,2

Most neonatal intensive care units in the USA do not screen breastmilk for the presence of the CMV virus. Freezing/thawing of breastmilk helps to diminish transmission of CMV from breastmilk. Pasteurized banked donor milk is free of CMV virus.

Routine screening is not currently done. There is no absolute indication to pump and dump.


(1)          Bardanzellu, F.; Fanos, V.; Reali, A. Human Breast Milk-Acquired Cytomegalovirus Infection: Certainties, Doubts and Perspectives. Curr Pediatr Rev 2019, 15 (1), 30–41.

(2)          Lanzieri, T. M.; Dollard, S. C.; Josephson, C. D.; Schmid, D. S.; Bialek, S. R. Breast Milk-Acquired Cytomegalovirus Infection and Disease in VLBW and Premature Infants. Pediatrics 2013, 131 (6), e1937-1945.