Temporal changes in hyaluronan concentrations in preterm human milk

Human breast milk (HM) is the gold standard source of nutrition for infants and contains many bioactive components supporting intestinal development and host defense. The composition of these bioactives varies with gestational age (GA), lactation stage, maternal health, genetics, diet, and environmental exposures [ 1 ]. Hyaluronan (HA), a glycosaminoglycan in HM, has beneficial effects on epithelial barrier integrity, antimicrobial defense, and intestinal repair [ 2 ]. A prior study in term HM demonstrated HA concentrations are highest early in lactation and decline over time [ 3 , 4 ]. Given that GA at birth substantially influences milk composition, we sought to characterize longitudinal HA concentrations in preterm HM stratified by GA at delivery.