Autism results from an interplay between genetics and the environment, but it has been tough to nail down the environmental factors involved.

In mice exposed to maternal inflammation in the womb, a key chemical messenger never makes the switch from exciting brain signals to inhibiting them.

Rats exposed prenatally to a cocktail of ‘autoimmune’ molecules have altered levels of two types of compounds needed for brain development.

A pregnant mouse’s response to infection alters the immune cells in her pups’ brains, and this may contribute to their autism-like behaviors.

Fever in pregnant rats around the time of delivery disrupts their pups’ communication and social behavior.

A specially made ‘decoy’ protein prevents an immune molecule from crossing the placenta; the strategy may prevent the brain changes that lead to autism.

Nearly half of American children with autism aged 10 to 17 are overweight or obese.

Taking antidepressants during pregnancy is unlikely to raise the risk of having a child with autism.

High blood pressure, preterm birth and other pregnancy complications may increase the risk of autism.