High testosterone exposure in womb ‘ups risk of autism’

The study looked at 383 girls who had no diagnosis of autism.

Updated: Feb 07, 2011, 14:23 PM IST

Melbourne: A new study has found that high testosterone exposure in the womb increases the risk of autism in children.

Researchers at Fiona Stanley`s Telethon Institute for Child Health Research found that girls with autistic-like behaviours at age two had their first period about six months later than girls without the disorder`s symptoms.

The study looked at 383 girls who had no diagnosis of autism. At age two they were each given a rating for showing autistic-like behaviours such as avoiding looking people in the eye.

"These findings indicate that exposure to testosterone in the womb may be regulating both autism-like behaviours and the age of first period and that this may play a role in clinical autism," The Australian quoted lead researcher Andrew Whitehouse as saying.

Whitehouse added that the results were linked to the so-called "male brain theory" of autism, which suggests the behaviour disorder is an extreme form of male mental traits.

"Autism is a real male-dominated condition; it affects around four males to one female, but there are also characteristics of people with autism that are more male-like," he said.

"People have started thinking what might cause that, and the obvious candidate is male-type hormones and the most biologically active is testosterone."

Whitehouse’s team now plans to conduct a world-first study to further examine the link.