title: Breast feeding and cognitive development at age 1 and 5 years.
abstract: OBJECTIVE
  To examine whether duration of breast feeding has any effect on a child's cognitive or motor development in a population with favourable environmental conditions and a high prevalence of breast feeding.
  
  
  METHODS
  In 345 Scandinavian children, data on breast feeding were prospectively recorded during the first year of life, and neuromotor development was assessed at 1 and 5 years of age. Main outcome measures were Bayley's Scales of Infant Development at age 13 months (Mental Index, MDI; Psychomotor Index, PDI), Wechsler Preschool and Primary Scales of Intelligence (WPPSI-R), and Peabody Developmental Scales at age 5.
  
  
  RESULTS
  Children breast fed for less than 3 months had an increased risk, compared to children breast fed for at least 6 months, of a test score below the median value of MDI at 13 months and of WPPSI-R at 5 years. Maternal age, maternal intelligence (Raven score), maternal education, and smoking in pregnancy were significant confounders, but the increased risk of lower MDI and total IQ scores persisted after adjustment for each of these factors. We found no clear association between duration of breast feeding and motor development at 13 months or 5 years of age.
  
  
  CONCLUSIONS
  Our data suggest that a longer duration of breast feeding benefits cognitive development.
authors.affiliation: Department of Community Medicine, Norwegian University of Science and Technology, N-7489 Trondheim, Norway.
authors.forename: N K
authors.initials: NK
authors.lastname: Angelsen
authors.forename: T
authors.initials: T
authors.lastname: Vik
authors.forename: G
authors.initials: G
authors.lastname: Jacobsen
authors.forename: L S
authors.initials: LS
authors.lastname: Bakketeig
mesh_terms: D001942:Breast Feeding; D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D003071:Cognition / Q000502:physiology*; D004522:Educational Status; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008423:Maternal Age; D009035:Mothers; D011446:Prospective Studies; D011597:Psychomotor Performance / Q000502:physiology; D013223:Statistics as Topic; D013997:Time Factors; D014888:Wechsler Scales