President Donald Trump speaks during a memorial service honoring Charlie Kirk at State Farm Stadium in Glendale, Arizona, on Sept. 21, 2025.

WASHINGTON – President Donald Trump is expected to make an announcement about autism during a Sept. 22 afternoon White House event that he has called one of the biggest in the “history of the country."

“I think you’re going to find it to be amazing,” Trump told a memorial rally for Charlie Kirk in Glendale, Arizona, on Sept. 21. "I think we found an answer to autism."

Trump is set to make an announcement at 4 p.m. with Health and Human Services Secretary Robert F. Kennedy Jr. and Dr. Mehmet Oz, administrator of the Centers for Medicare and Medicaid Services.

The officials are expected to announce that Tylenol use during pregnancy could contribute to the development of autism in children, according to Politico and The Washington Post. Tylenol's owner, Kenvue, said in a statement the active ingredient "acetaminophen does not cause autism."

Trump and his advisers are also expected to discuss a potential treatment for autism, the drug leucovorin, the news organizations reported.

Here is what we know about the announcement:

Trump to cite ‘gold standard’ medical research into autism: Leavitt

White House press secretary Karoline Leavitt declined to preview what President Donald Trump would announce about autism, but said Health Secretary Robert F. Kennedy Jr. was “paying attention to studies and the gold standard of science and research” that others have ignored.

“The president is very excited about this,” Leavitt told reporters at the White House. “I don’t want to scoop the president of the United States and our secretary of health and human services.”

“I think Americans are going to be enlightened and proud by what they hear,” Leavitt added. - Bart Jansen

How to watch Trump’s autism announcement

Trump’s announcement about autism is scheduled for 4 p.m. ET on Sept. 22. USA TODAY is set to stream the announcement live here. - Bart Jansen

Autism is increasingly diagnosed

Autism spectrum disorder is the clinical name for the condition most people refer to as autism and is diagnosed based on challenges with social skills, communication and repetitive behaviors. Symptoms vary widely on the spectrum, with some people unable to communicate at all and others highly successful.

Autism diagnoses nationwide have increased significantly since 2000. By 2020, the U.S. autism rate in 8-year-olds was 1 in 36, or 2.77%, up from 0.66% in 2000, according to the Centers for Disease Control and Prevention.

Research spanning decades hasn’t yielded firm answers on what contributes to autism, but many scientists believe genetics play a role, potentially in combination with environmental influences. Kennedy has argued the country has an "autism epidemic" fueled by "environmental toxins."

Because traits and support levels vary widely, "no single approach fits all people with autism," says Christopher Banks, president and CEO of the Autism Society of America.

'Acetaminophen does not cause autism': Tylenol

Tylenol parent company Kenvue issued a statement saying independent scientific research shows that taking acetaminophen is "the safest pain reliever option for pregnant women as needed throughout their entire pregnancy."

The company said that a decade of rigorous research endorsed by leading medical professionals and global health regulators found "no credible evidence linking acetaminophen to autism."

“We believe independent, sound science clearly shows that taking acetaminophen does not cause autism," the statement said. "We strongly disagree with any suggestion otherwise and are deeply concerned with the health risk this poses for expecting mothers."

Still, more than two dozen studies around the world have linked a pregnant person's frequent use of acetaminophen to autism and attention-deficit hyperactivity disorder in their child.

But several studies have also found competing evidence. A 2024 study in Sweden of about 2 million children, over 180,000 of whom were exposed to acetaminophen during pregnancy, found no associations between the pain medication and children’s risk of autism, ADHD or intellectual disability.

A federal judge ruled that 440 lawsuits against Tylenol makers do not have "admissible evidence" showing a link between prenatal use of Tylenol and autism or ADHD, according to reporting by ABC News. −Zac Anderson and Adrianna Rodriguez

No 'sound-bite answer to what causes autism': expert

Trump signed an executive order in February creating the Make America Healthy Again Commission, which included studying the threats of certain medications.

Kennedy said at an April news conference that autism was "preventable" and he directed the National Institutes of Health to “identify precisely what the environmental toxins are that are causing it.”

The Centers for Disease Control and Prevention previously found that the rising incidence of autism could be attributed to more access to diagnostic tools and improvements in early detection. Some people with autism spectrum disorder have a genetic condition while other “causes are not yet known,” according to the CDC.

"There will never be a sound-bite answer to what causes autism,” Helen Tager-Flusberg, a psychologist who studies neurodevelopmental conditions at Boston University, Massachusetts, told Nature magazine. − Swapna Venugopal Ramaswamy

What do doctors say about Tylenol?

Medical guidelines say acetaminophen, the generic form of Tylenol, is safe to use. Acetaminophen is commonly used by pregnant women, who are already advised by the Food and Drug Administration not to use ibuprofen after 20 weeks of pregnancy.

The Society for Maternal-Fetal Medicine and the American College of Obstetricians and Gynecologists both endorsed using acetaminophen during pregnancy in Sept. 5 statements.

“Acetaminophen remains a safe, trusted option for pain relief during pregnancy,” the statement said. “Despite recent unfounded claims, there’s no clear evidence linking prudent use to issues with fetal development.”

Contributing: Daryl Austin, USA TODAY; Reuters

This article originally appeared on USA TODAY: Trump expected to announce 'answer' to autism, blame Tylenol: Live updates

Reporting by Bart Jansen, Zac Anderson and Swapna Venugopal Ramaswamy, USA TODAY / USA TODAY

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