Foetal testosterone and autistic traits

Background: Studies of amniotic testosterone in humans suggest that foetal testosterone (fT) is related to specific (but not all) sexually dimorphic aspects of cognition and behaviour. It has also been suggested that autism may be an extreme manifestation of specific (but not all) male-typical traits, both in terms of cognition and neuroanatomy. Objectives: To test if fT levels are associated with individual differences in autistic traits, fT levels were measured in amniotic fluid from pregnant women following routine amniocentesis. Methods: Two instruments measuring number of autistic traits (the Childhood Autism Spectrum Test (CAST) and the Child Autism Spectrum Quotient (AQ-Child)) were completed by these women about their children (n=225), ages 6-10 yrs. Results: fT levels were positively associated with higher scores on the CAST and AQ-Child. This relationship was seen within sex as well as when the sexes were combined, suggesting this is an effect of fT rather than of sex. Conclusions: These findings are consistent with the hypothesis that prenatal androgen exposure is related to the number of autistic traits a child exhibits. Present results need to be followed up in a much larger sample to test if clinical cases of autism have elevated fT.