Clearing Up Misinformation About Autism

For decades, misinformation has surrounded autism — especially when it comes to its causes. Many people have heard claims linking autism to vaccines, Tylenol use during pregnancy, or even poor parenting. These ideas, while widespread, are not supported by science and can create unnecessary fear and stigma for families. 

The Role of Genetics 

The strongest scientific evidence points to genetics as the biggest factor in autism. Research shows autism is highly heritable, with estimates suggesting genetics account for 50–90% of cases. This includes both inherited genes and new, spontaneous genetic changes. Environmental factors, like prenatal health or parental age, may also play a role, but they interact with — rather than replace — the genetic foundation. 

Vaccines and Autism 

The idea that vaccines cause autism has been thoroughly debunked. Large-scale research studies have found no connection between the two. The original author of a study that proposed the link has since been disgraced as having fabricated results. The rise in autism diagnoses over the past several decades is better explained by greater awareness, better screening, and expanded diagnostic criteria — not by vaccines or other routine medications. 

Tylenol During Pregnancy 

More recently, concerns have been raised about the use of acetaminophen (Tylenol) during pregnancy. Scientists caution against drawing strong conclusions because many of the studies that raise alarms have flaws in how the data was collected. While some studies suggest there may be a connection between frequent use of Tylenol and autism or ADHD, other large and well-designed studies have found no such link. At this point, there is no clear evidence that Tylenol causes autism. Doctors still often recommend it because untreated pain or fever during pregnancy can also carry risks. 

An important aspect of having Autism is increased sensitivity to pain. Therefore, someone is pregnant and has Autism, they are already both more likely to have an Autistic child due to the genetic causes. Inconsequential to having a child with Autism, the pregnant person is more likely to need to use Tylenol due to their increased sensory sensitivities common to Autism. 

It’s the Autism that likely causes the increased Tylenol use. Not the other way around. 

Sensory Sensitivities and Health Care 

Herein lies the piece of the autism conversation that is often overlooked: the lived experiences of autistic individuals. Many report heightened sensitivity to light, sound, touch, or pain, which can make everyday experiences — including pregnancy and medical care—especially challenging. Clear communication and awareness from health professionals can go a long way in reducing stress and reducing shame around parents “causing” autism. 

The Bottom Line 

Autism is complex, but it is not caused by vaccines, poor parenting, or any single medication. While profound or Level 3 Autism can be extremely challenging for some families, labeling Autism as a tragedy is demeaning to millions of people on the spectrum who have embraced their quirks and wouldn’t trade their Autism for the world. It is primarily rooted in genetics, shaped by a combination of inherited genes and spontaneous gene factors. While researchers continue to study how genetics and environment interact, one thing is certain: spreading accurate information is vital. By challenging myths and focusing on what science actually shows, we can reduce fear, stigma, and confusion — supporting autistic individuals and their families with understanding, acceptance, and compassion. 

Hanna Knudsen, MS CMHC, LCPC 

References 

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Autism Speaks statement on Tylenol and leucovorin. (2025, September 22). https://www.autismspeaks.org/news/autism-speaks-statement-tylenol-and-leucovorin 

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