title: Maternal and Infant Secretory Immunoglobulin A across the Peripartum Period.
abstract: BACKGROUND
  Salivary secretory immunoglobulin A (sIgA) concentrations change over early infancy. The primary immunoglobulin in breast milk is sIgA, however, no study has examined the role of maternal sIgA in relation to infant salivary sIgA.
  
  
  OBJECTIVE
  This study aimed to examine within-source associations and mean level changes of maternal and infant sIgA across the first 6 months of life, to examine the interrelations between maternal and infant sIgA across the first 6 months of life, and to determine the association between breastfeeding and infant sIgA.
  
  
  METHODS
  Participants were a convenience sample of 51 mother-infant dyads. Salivary sIgA was collected from the mother in the third trimester. Infant and maternal salivary and maternal breast milk sIgA was collected at approximately 1, 3, and 6 months postpartum.
  
  
  RESULTS
  Maternal salivary sIgA showed no mean level change across the visits, and levels were moderately associated over time. Breast milk sIgA was moderately associated over time; infant salivary sIgA was weakly associated over time. Both breast milk and infant sIgA levels decreased from 1 to 3 months postpartum. Maternal salivary sIgA was not related to infant or breast milk sIgA. Breastfed infants had lower levels of salivary sIgA. Likewise, higher concentrations of breast milk sIgA were related to lower concentrations of infant sIgA.
  
  
  CONCLUSIONS
  Maternal salivary sIgA is highly stable over the peripartum period, whereas breast milk and infant salivary sIgA was variable. Infant secretory IgA development does not depend positively on maternal salivary or breast milk sIgA.
authors.affiliation: Department of Human Ecology, University of California, Davis, CA, USA lchibel@ucdavis.edu.
authors.forename: Leah C
authors.initials: LC
authors.lastname: Hibel
authors.affiliation: Department of Human Ecology, University of California, Davis, CA, USA.
authors.forename: Hillary
authors.initials: H
authors.lastname: Schiltz
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D005260:Female; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000378:metabolism*; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D008895:Milk, Human / Q000276:immunology*; D058725:Peripartum Period / Q000276:immunology*; D049590:Postpartum Period / Q000276:immunology*; D012463:Saliva / Q000276:immunology*
chemical_list: D015415:Biomarkers; D007071:Immunoglobulin A, Secretory
keywords: breast milk; breastfeeding; immunity; mothers and infants; salivary sIgA