Secretory immunoglobulin A in preterm infants: determination of normal values in breast milk and stool.
Claire L GrangerChristopher A LambNicholas D EmbletonLauren C BeckAndrea C MasiJeremy M PalmerChristopher J StewartJanet E BerringtonPublished in: Pediatric research (2021)
(Secretory) Immunoglobulin A (IgA) is present in colostrum of maternal milk from infants as preterm as 23-24 weeks gestational age, falling over the first 3 weeks to steady levels similar to term. Gestation at birth does not impact (secretory) IgA levels in breast milk. IgA is present in very preterm infant stools from maternal milk fed infants from the first week of life, but not in formula milk fed preterm infants until week three, suggesting endogenous production from this point. Refrigeration, freezing, and feeding via plastic tubing approximately halved the amount of IgA available.