What Causes Autism?

No single cause has been determined to lead to autism.  Most researchers believe a combination of genetic and environmental factors are responsible for the disorder.

Here is what researchers know:

1. Heredity—Several studies involving twins show that autism can be passed down through families.  Other studies have scientists thinking that parents who have one child with autism may have a slightly higher risk of having another autistic child.
2. Medical conditions—People who have certain conditions like Fragile X syndrome (most common form of inherited mental retardation) may be at a higher risk for autism.  
3. Environmental factors—Researchers are checking into several factors that may cause problems during the brain’s development such as viral infections, exposure to certain chemicals and imbalances in metabolism.
4. Pregnancy problems— Even the slightest disturbance during pregnancy may cause problems.  Scientists are studying mothers’ health during pregnancy along with  problems during the delivery for clues as to what might cause autism.   According to recent research, harmful substances taken during pregnancy may result in a higher risk of autism.