The rise in autism

When I was growing up in the 1940s and ‘50s, I never knew anyone—or of anyone—who was autistic. Now, off the top of my head, I can name three people who have autistic grandchildren. The rise in autism has commonly been attributed to better record keeping. I never believed this.

During the 1970s, three in 10,000 children were diagnosed with autism. According to the CDC, in 2025, one in 31 U.S. children aged eight are identified with autism spectrum disorder. 

New research, which I learned about from alert reader Don Jordan, indicates that certain drugs, taken during pregnancy, are at least partially responsible for the rise in autism. The drugs in question are those that inhibit the synthesis of sterols—in this case, cholesterol.

The medications include SSRIs, such as Fluoxetine; antipsychotics, such as haloperidol; beta blockers, such as metropole; statins, such as simvastatin; and others, including trazodone, bupropion, and buspirone.

The research, published in Molecular Psychiatry, is based on a study of more than six million pregnancies spanning all fifty states over ten years. Roughly 11 percent of pregnant women studied were prescribed at least one of these drugs. The researchers found 234,971 children with an autism diagnosis.

The article states, “Cholesterol is essential for life, serving as a critical structural component of all cells.…Cholesterol biosynthesis is particularly critical during intrauterine development in all vertebrates.” (Our brains are the most cholesterol-rich organs in our bodies.)

Other studies have shown that “maternal inflammation” contributes to the rise in autism. For example, scientists have found that a mother who is diagnosed with asthma or allergies during the second trimester more than doubles the unborn child’s risk of autism. Other studies have shown that mothers of autistic children tended to have more autoimmune disorders such as rheumatoid arthritis and celiac disease. The idea is that the mother’s inadequately controlled inflammatory responses can predispose autism in the child. (The spinal fluid of autistic people has shown elevated markers of inflammation.)  

These statistics are alarming. One scientist notes that “Something environmental is causing the rise.” But what?

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