RFK Jr autism report: Could a common painkiller taken during pregnancy be a factor?

The United States Department of Health and Human Services (HHS) is preparing to release a report this month targeting autism and its possible causes.

US Health Secretary Robert F Kennedy Jr, who has been leading the initiative, has for months promised that the federal government will soon provide answers to what he calls America’s “autism epidemic.”

According to The Wall Street Journal, the upcoming report may single out the widespread use of Tylenol — a commonly used over-the-counter painkiller whose active ingredient is acetaminophen — during pregnancy as a potential factor linked to autism in children.

Low levels of folate, an essential B vitamin crucial for fetal development, are also expected to be highlighted. Folate has long been recommended for pregnant women to prevent birth defects of the brain and spine, such as spina bifida.

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The prospect of a federal agency suggesting a connection between a drug used by millions of expectant mothers and the rise in autism rates has triggered concern across the medical community.

How did autism come under the lens by RFK Jr?

In April, Kennedy announced what he described as a “massive testing and research effort” aimed at identifying the factors behind the sharp increase in autism diagnoses in the US.

Speaking at a Cabinet meeting with US President Donald Trump, Kennedy declared, “By September, we will know what has caused the autism epidemic and we’ll be able to eliminate those exposures.”

Trump, during the same meeting, remarked, “There has to be something artificial causing this, meaning, a drug or something.”

Kennedy later elaborated in a Fox News interview, saying the investigation would not be limited to a single area of research, “We’re going to look at vaccines, but we’re going to look at everything. Everything is on the table, our food system, our water, our air, different ways of parenting, all the kind of changes that may have triggered this epidemic.”

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The US National Institutes of Health (NIH) was allocated $50 million to support this unprecedented inquiry. Thousands of researchers from top universities and institutions submitted proposals, and up to 25 research teams are expected to receive grants to further explore autism-related risk factors.

This funding supplements the NIH’s existing $300 million annual budget dedicated to autism research.

What is the potential link between Tylenol and autism?

The Wall Street Journal reported on Friday, that the HHS report is expected to focus in part on the role of acetaminophen use during pregnancy.

Tylenol, which contains acetaminophen, is one of the most widely consumed medications in the United States and is frequently used by pregnant women to treat pain and fever.

The report will reportedly examine whether exposure to acetaminophen in utero, combined with low maternal folate levels, could increase the risk of a child developing autism.

It will also reference folinic acid, also known as leucovorin, as a potential intervention to help alleviate autism symptoms in some individuals.

Andrew Nixon, a spokesperson for HHS, pointed out that the department has not confirmed any specific findings and urged the public to wait for the official release.

“We are using gold-standard science to get to the bottom of America’s unprecedented rise in autism rates. Until we release the final report, any claims about its contents are nothing more than speculation,” Nixon said.

Despite the cautionary statement, anticipation about the report has been building. Earlier in the week, far-right activist Laura Loomer suggested on social media that HHS was investigating Tylenol use during pregnancy.

NEW:

ATTENTION TO EVERYONE WHO HAS EVER TAKEN TYLENOL OR KNOWS SOMEONE WITH AUTISM

🚨 Link Between Prenatal Tylenol @tylenol Use and Autism Rates Under Scrutiny as @HHSGov Prepares Major September Announcement On Autism Interventions 🚨

As autism rates continue to climb across… pic.twitter.com/08XNwuU4sS

— Laura Loomer (@LauraLoomer) September 2, 2025

On the same day, Dr. Robert Malone, a controversial figure whom Kennedy recently appointed to the CDC’s independent vaccine advisory committee, speculated on One America News Network that the forthcoming report might draw connections between Tylenol, vaccines, and autism.

Kenvue, the pharmaceutical company that manufactures Tylenol, rejected the suggestion of any link.

“Nothing is more important to us than the health and safety of the people who use our products. We have continuously evaluated the science and continue to believe there is no causal link between acetaminophen use during pregnancy and autism,” the company said in a statement.

What does science & research say?

The possible relationship between acetaminophen exposure during pregnancy and neurodevelopmental outcomes, including autism, has been studied for years, but results have been inconsistent and often contradictory.

A significant study published in JAMA in 2024 involved data from over two million children born in Sweden between 1995 and 2019.

Among these, about 185,000 children were born to mothers who reported using acetaminophen during pregnancy.

Initially, researchers observed a slight increase in autism diagnoses in this group.

However, when they compared siblings within the same family — one exposed to the drug in the womb and another who was not — they found no association between acetaminophen and autism, ADHD, or intellectual disabilities.

Brian Lee, an epidemiologist at Drexel University and one of the study’s authors, highlighted the importance of this intra-family comparison. “We were able to adjust for things that we saw that other people might have missed before,” Lee explained.

In contrast, a separate meta-analysis published in BMC Environmental Health in August analysed 46 different studies examining acetaminophen use during pregnancy and childhood neurodevelopmental disorders.

Six of these studies focused specifically on autism.

The review concluded that there was “strong evidence of an association” between prenatal acetaminophen exposure and autism. However, the authors stressed that their analysis could not prove causation.

“We recommend judicious acetaminophen use — lowest effective dose, shortest duration — under medical guidance, tailored to individual risk–benefit assessments, rather than a broad limitation,” they wrote.

Earlier assessments by health agencies have similarly struggled to establish clear conclusions.

In 2015, the US Food and Drug Administration (FDA) evaluated the available research and concluded that methodological flaws made it impossible to confirm or rule out a link. As a result, no changes were made to painkiller usage recommendations during pregnancy.

In 2017, the Society for Maternal-Fetal Medicine reviewed the issue and stated that the “weight of evidence is inconclusive regarding a possible causal relationship between acetaminophen use and neurobehavioural disorders in the offspring.”

The Autism Science Foundation echoed these findings in a recent statement.

“Any association between acetaminophen and autism is based on limited, conflicting, and inconsistent science and is premature given the current science. … The Autism Science Foundation strongly supports research into autism’s causes. More research needs to be done before alarming families or suggesting steps that may not actually reduce risk.”

Why are autism rates rising in the US?

Autism spectrum disorder diagnoses have surged in recent decades. According to the CDC, by 2022, approximately one in 31 children in the US was diagnosed with autism by age eight, compared to one in 36 in 2020.

Experts point to several factors driving this increase. Dr. Christine Ladd-Acosta, vice director of the Wendy Klagg Center for Autism at Johns Hopkins, explained two main reasons on the Public Health on Call podcast.

First, the definition of autism was broadened in 2013 by the psychiatric community, resulting in more individuals qualifying for a diagnosis.

Second, there has been a concerted effort to improve early screening, especially in infants and toddlers, leading to earlier and more frequent detection.

These efforts have also reduced stigma surrounding autism, encouraging more families to seek evaluations and support services.

“The push for increased awareness of the symptoms has been accompanied by a greater acceptance of the disorder, so people are not as afraid to seek help or to be identified as having autism,” Ladd-Acosta said.

Why is RFK Jr’s approach controversial?

While Kennedy has pledged to uncover the root causes of autism, his approach has faced criticism from autism advocacy organisations and medical experts.

Many scientists caution against the notion of a single cause for autism, noting that it is a complex condition with a wide range of presentations and underlying risk factors.

The Autism Society of America condemned Kennedy’s initiative in a strongly worded statement, “It is neither a chronic illness nor a contagion,” the organization said, calling the effort “harmful, misleading, and unrealistic.”

Kennedy has long promoted debunked theories linking vaccines to autism, despite overwhelming scientific evidence disproving such claims.

Medical professionals point out that most identified risk factors for autism exist before birth. These include prenatal exposure to pesticides and air pollution, premature birth, low birth weight, maternal health issues during pregnancy, and parental age at conception.

The NIH lists these factors as areas of ongoing study.

For decades, acetaminophen has been regarded as one of the safest pain relief options for pregnant women. Doctors typically advise its use over other painkillers such as nonsteroidal anti-inflammatory drugs (NSAIDs), which carry known risks during pregnancy.

Until definitive evidence is available, experts advise pregnant women to follow existing guidelines: use acetaminophen only when necessary, at the lowest effective dose, and under medical supervision.

They also recommend maintaining adequate folate intake through a balanced diet and prenatal supplements, a practice already endorsed to prevent neural tube defects.

With inputs from agencies