Poll: After President Trump’s Warning, Many People Are Uncertain About Whether Tylenol Use in Pregnancy Causes Autism; Most Republicans Say It Is Probably or Definitely True

Following the Trump administration’s warning last month that using acetaminophen – the active ingredient in Tylenol – during pregnancy can increase the risk of autism in children, very few (4%) adults say the claim about a causal relationship is “definitely true,” a new KFF Tracking Poll on Health Information and Trust finds.

About a third (35%) of the public says the claim of such a link is “definitely false”, while most people are uncertain what to believe, with equal shares saying it is “probably true” and “probably false” (30% in each case).

The administration’s claim of a Tylenol-autism link came despite mixed results in past studies about an association between the two. Major medical groups and researchers cautioned the public that there isn’t a proven cause-and-effect link.

Partisanship plays a major role in public perception of this claim, which was announced at a White House event with President Trump and Health and Human Services Secretary Robert F. Kennedy Jr.

Democrats (59%) are much more likely than Republicans (12%) to say this claim is “definitely false.” Conversely, most Republicans (56%) say they believe the claim is either “definitely” or “probably” true.

Secretary Kennedy and the Trump administration have also been pursuing dramatic changes in the nation’s vaccine policy, including narrowing recommendations for the COVID-19 vaccine, moving to revise the pediatric vaccine schedule, and the August firing of the director of the Centers for Disease Control and Prevention (CDC).

The latest poll shows that the public’s trust in the CDC continues to slide and is now at its lowest level since the start of the COVID-19 pandemic. Half of the public now say they have “a great deal” (18%) or “a fair amount” (32%) of trust in the CDC to provide reliable vaccine information, down from 57% in July and 63% in September 2023.

Among partisans, Democrats remain the most likely to say they trust the CDC on vaccines (64%), though that is down 24 percentage points since 2023. Among independents, nearly half (47%) say they trust the CDC on vaccines, down from 61% in 2023, while the share of Republicans who trust the CDC’s vaccine information is lower (39%) but similar to where it stood in 2023 (40%).

Compared to the CDC, more people say they trust the American Academy of Pediatrics (69% of parents) and the American Medical Association (64% of all adults) to provide reliable information about vaccines, two groups that have recently been removed from federal vaccine working groups.

“It’s encouraging if far from ideal that as trust in our nation’s scientific agencies crumbles, the public does trust the professional associations who have stepped forward,” KFF President and CEO Drew Altman said.

Other findings include:

• The poll finds 43% of the public consider themselves supporters of the “Make America Healthy Again” (MAHA) movement, championed by President Trump and Secretary Kennedy. Two-thirds (66%) of MAHA supporters are Republicans or Republican-leaning independents, including 59% who also identify as supporters of the president’s “Make America Great Again” movement. Far fewer are Democrats (20%) or non-leaning independents (13%).
• Most (59%) of the public disapproves of Secretary Kennedy’s overall job performance, and a similar share (62%) disapproves of the way he is handling vaccine policy. Partisans divide on both questions, with Republicans largely approving, and Democrats and independents largely disapproving.
• With Florida taking steps to end its school vaccine mandates, most parents nationally (70%) say they are opposed to removing public school vaccine requirements in their state. More than half of parents (56%) say getting children vaccinated is part of parent’s responsibility to protect the health of others, more than the share (44%) who say it is a personal choice. Republican parents (62%) are far more likely than Democratic parents (26%) to see vaccinating children as a personal choice.

Designed and analyzed by public opinion researchers at KFF, this survey was conducted September 23-29, 2025, online and by telephone among a nationally representative sample of 1,334 U.S. adults in English and in Spanish. The margin of sampling error is plus or minus 3 percentage points for the full sample. For results based on other subgroups, the margin of sampling error may be higher.