Causes and Risk FactorsWe do not know all of the causes of ASDs. However, we have learned that there are likely many causes for multiple types of ASDs. There may be many different factors that make a child more likely to have an ASD, including environmental, biologic and genetic factors.
- Most scientists agree that genes are one of the risk factors that can make a person more likely to develop an ASD.
- Children who have a sibling or parent with an ASD are at a higher risk of also having an ASD.
- ASDs tend to occur more often in people who have certain genetic or chromosomal conditions. About 10% of children with ASDs also have been identified as having Down syndrome, fragile X syndrome, tuberous sclerosis, or other genetic and chromosomal disorders.
- When taken during pregnancy, the prescription drugs valproic acid and thalidomide have been linked with a higher risk of ASDs.
- We know that the once common belief that poor parenting practices cause ASDs is not true.
- There is some evidence that the critical period for developing ASDs occurs before birth. However, concerns about vaccines and infections have led researchers to consider risk factors before and after birth.
- A small percentage of children who are born prematurely or with low birthweight are at greater risk for having ASDs.ASDs continue to be an important public health concern. Like the many families living with ASDs, CDC wants to find out what causes the disorder. Understanding the risk factors that make a person more likely to develop an ASD will help us learn more about the causes. We are currently working on one of the largest U.S. studies to date, called Study to Explore Early Development (SEED). SEED is looking at many possible risk factors for ASDs, including genetic, environmental, pregnancy, and behavioral factors.
I laughed when I first read that bullet point I highlighted. Took a team of lawyers to craft that one, now didn't it!
Screen shot for posterity. Full size here.