Microorganisms in human milk: lights and shadows

Elisa Civardi1, Francesca Garofoli, Chryssoula Tzialla

  • 1Neonatal Unit and Neonatal Intensive Care Unit, Maternal-Infant Department, Fondazione IRCCS Policlinico San Matteo , Pavia , Italy .

Human milk has been traditionally considered germ free, however, recent studies have shown that it represents a continuous supply of commensal and potentially probiotic bacteria to the infant gut. Mammary microbioma may exercise anti-infective, anti-inflammatory, immunomodulatory and metabolic properties. Moreover human milk may be a source of pathogenic microorganism during maternal infection, if contaminated during expression or in case of vaccination of the mother. The non-sterility of breast milk can, thus, be seen as a protective factor, or rarely, as a risk factor for the newborn.

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