Exposure to Prenatal Testosterone Linked to Autistic Traits

by VR Sreeraman on Sep 12 2007 6:38 PM

A study by Cambridge University researchers suggests that children who have faced exposure to higher levels of testosterone in the womb may develop autistic traits.

The suggestion has come from the researchers who have been tracking a group of children since birth. The children are 8-year-olds at present.

The researchers say that questionnaires filled out by parents show that children who had experienced higher levels of testosterone in the womb generally have better pattern recognition and numerical skills, such as remembering car number plates. These children, however, are less keen on socialising, they add.

Whereas none of the kids was diagnosed with autism, the researchers said that the aforesaid traits, when taken to an extreme, were often present in autistic children.

The researchers measured the level of testosterone in samples of amniotic fluid from 235 women who got the tests done for other clinical reasons, and they have been following the development of some of the children ever since.

The researchers had previously reported that babies who had experienced higher levels of testosterone in the womb tended to look at their mother less often when they were 12 months old. They also said that at 18 months, such children were more likely to have a smaller vocabulary than the others.

Now, the latest update on the children’s progress presented at the British Association's Festival of Science in York by Simon Baron-Cohen suggests that the correlation between foetal hormone levels and autistic-trait behaviour continues as kids grow up.

Links between testosterone and autistic traits have been suggested before, and found in animal studies. The Cambridge study is starting to show biological evidence to back up the theories.

However, the researchers have yet not found any cogent evidence that testosterone levels actually cause autism, reports Nature magazine.

Baron-Cohen's team is now embarking on the mammoth task of comparing data from 90,000 amniotic fluid samples from the National Danish Biobank with psychiatric records, to check for association between testosterone and diagnosis of autism.