title: Sex-specific associations between umbilical cord blood testosterone levels and language delay in early childhood.
abstract: BACKGROUND
  Preliminary evidence suggests that prenatal testosterone exposure may be associated with language delay. However, no study has examined a large sample of children at multiple time-points.
  
  
  METHODS
  Umbilical cord blood samples were obtained at 861 births and analysed for bioavailable testosterone (BioT) concentrations. When participating offspring were 1, 2 and 3 years of age, parents of 767 children (males = 395; females = 372) completed the Infant Monitoring Questionnaire (IMQ), which measures Communication, Gross Motor, Fine Motor, Adaptive and Personal-Social development. Cut-off scores are available for each scale at each age to identify children with 'clinically significant' developmental delays. Chi-square analyses and generalized estimating equations examined longitudinal associations between sex-specific quartiles of BioT concentrations and the rate of developmental delay.
  
  
  RESULTS
  Significantly more males than females had language delay (Communication scale) at age 1, 2 and 3 years (p-values ≤. 01). Males were also more likely to be classified as delayed on the Fine-Motor (p = .04) and Personal-Social (p < .01) scales at age 3 years. Chi-square analyses found a significant difference between BioT quartiles in the rate of language delay (but not Fine-Motor and Personal-Social delay) for males (age 3) and females (age 1 and 3). Generalized estimating equations, incorporating a range of sociodemographic and obstetric variables, found that males in the highest BioT quartile were at increased risk for a clinically significant language delay during the first 3 years of life, with an odds ratio (OR) of 2.47 (95% CI: 1.12, 5.47). By contrast, increasing levels of BioT reduced the risk of language delay among females (Quartile 2: OR = 0.23, 95% CI: 0.09, 0.59; Quartile 4: 0.46, 95% CI: 0.21, 0.99).
  
  
  CONCLUSIONS
  These data suggest that high prenatal testosterone levels are a risk factor for language delay in males, but may be a protective factor for females.
authors.affiliation: Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, 100 Roberts Road, Subiaco, WA 6008, Australia. awhitehouse@ichr.uwa.edu.au
authors.forename: Andrew J O
authors.initials: AJ
authors.lastname: Whitehouse
authors.forename: Eugen
authors.initials: E
authors.lastname: Mattes
authors.forename: Murray T
authors.initials: MT
authors.lastname: Maybery
authors.forename: Michael G
authors.initials: MG
authors.lastname: Sawyer
authors.forename: Peter
authors.initials: P
authors.lastname: Jacoby
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Keelan
authors.forename: Martha
authors.initials: M
authors.lastname: Hickey
mesh_terms: D000328:Adult; D000367:Age Factors; D016009:Chi-Square Distribution; D002675:Child, Preschool; D004522:Educational Status; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D006801:Humans; D007223:Infant; D007805:Language Development Disorders / Q000097:blood*; D008297:Male; D008423:Maternal Age; D015999:Multivariate Analysis; D016017:Odds Ratio; D011446:Prospective Studies; D011581:Psychological Tests; D012737:Sex Factors; D011795:Surveys and Questionnaires; D013739:Testosterone / Q000097:blood* / Q000502:physiology; D055815:Young Adult
chemical_list: D013739:Testosterone