Improved feeding tolerance and growth linked to gut microbial diversity in very-low-birthweight infants fed with mother's own milk vs donor milk.

Abstract

Early infant nutrition plays a crucial role in shaping future health,1 and human milk is the first choice for all infants. It has numerous benefits, including improved neurological, immunological or metabolic outcomes, and makes a significant contribution to early intestinal microbiome development.2-4 Mother's own milk is even more important for preterm infants, as they frequently have a different gut microbiota to term infants, with reduced species diversity. This makes them more vulnerable to serious intestinal inflammatory conditions like necrotising enterocolitis.5, 6 Numerous studies have demonstrated the benefits of feeding human milk, rather than formula, in intensive care units, but there has been a lack of studies comparing maternal and donor milk.7, 8 The Ford et al study was the first to compare the development of intestinal microbiota and clinical outcomes in infants with an exclusive human milk diet of mother's own milk or donor milk. They enrolled 125 infants born weighing less than 1500 g, without barriers for enteral feeding, and grouped them based on which milk accounted for more than 50% of their diet. Their results highlight several points. First, infants fed mother's own milk or donor milk had significantly different microbiota at the phylum and genius level by four and six weeks of life. Those fed with mother's own milk had increased microbial diversity and an abundance of beneficial bacteria, such as Bifidobacterium (P = .02) and Bacteroides (P = .04) that protect against severe morbidities. Second, they were 60% less likely to experience feeding intolerance than those who received donor milk, leading to improved growth parameters. This was consistent with previous studies that suggested possible explanations, such as lower protein content in donor milk or diminished lipase activity due to pasteurisation.3, 9 Third, mother's own milk consistently protected the gut microbiota from the effect of antibiotics, which may have important clinical implications. The study strengths were the large sample size, longitudinal design and multiple microbiota assessments, while the limitations were its observational design and the inability to account for confounding variables and other potential sources of bias. The study adds additional data to the benefits of mother's own milk for very-low-birthweight infants and further supports efforts to improve lactation in neonatal care units and maintain the mother's milk supply during extended hospital stays. However, further research is needed on the beneficial effects of probiotics, adjusted by feeding type, on microbiological and clinical outcomes. It is plausible that nutrition and probiotic supplementation may act together in the preterm infant's gut, leading to a global improvement in neonatal health. https://ebneo.org/2019/10/gut-microbial-diversity/ The authors declare no conflict of interest.