While the White House last month stressed a possible
connection between Tylenol use among pregnant woman and autism, the body of
research paints a far more complex reality.
Editor’s Note: The following piece covers statements made
by the White House last month regarding Tylenol use and a link to autism, and
research carried out by scientists exploring that connection. This piece does
not offer medical advice, and people should always defer to their physician on
matters of care and medication.
On Monday the White House released a statement saying that “Evidence
Suggests Link Between Acetaminophen, Autism.” That announcement drew rebuke
from a number of quarters, including the Society
for Maternal-Fetal Medicine, which released a statement saying, in part:
To be clear, SMFM stands behind our recommendation that
acetaminophen use during pregnancy has not been shown to cause or increase the
risk of autism or other neurobehavioral problems in children.
On Monday evening, the Advance joined a call sponsored by
SciLine featuring Dr. Brian Lee of Drexel University. Lee is co-author of a
study published last year in JAMA, “Acetaminophen
Use During Pregnancy and Children’s Risk of Autism, ADHD, and Intellectual
Disability,” which followed 2,480,797 children born between 1995 and 2019
in Sweden, with follow-up through December 31, 2021
That study concluded that “Acetaminophen use during
pregnancy was not associated with children’s risk of autism, ADHD, or
intellectual disability in sibling control analysis.”
Understanding the discrepancy in these positions requires
better understanding the research being cited.
Apples to Oranges
Lee said that the study published in JAMA by himself and his
coauthors is a “two-part story.”
When Lee and his coauthors looked at the kids of mothers who
used acetaminophen, the active ingredient in Tylenol, during pregnancy and
those who didn’t use acetaminophen, “we found a slight statistical increase in
risk of autism and ADHD.”
But does this mean that acetaminophen is causing autism and
ADHD?
“When we look at users [of acetaminophen] versus non-users,”
Lee said, “this is kind of an apples to oranges comparison because the users
are so different in many ways.”
He notes, for example, that people taking acetaminophen are
sicker than those who aren’t taking the medicine because “they have a medical
condition that needs treatment.”
The other issue concerns the connection between
neurodevelopmental disorders and genetics.
“Autism is a highly heritable condition,” Lees said, “and …
when you just look at users versus non-users, it sort of ignores that aspect.”
Apples to Apples
To ensure their study accounted for genetics and, thus, was
comparing apples to apples, Lee and his coauthors “looked at siblings born to
the same mother,” he said, where “one sibling was exposed and the other sibling
was unexposed.”
Under these conditions, Lee said, “the apparent risk
completely flatlined and disappeared. In other words, there was no increase in
risk of autism or ADHD associated with acetaminophen use. And what that told us
was that familial confounding factors such as maternal genetics were likely
explaining the apparent statistical association.”
What about Leucovorin?
Prior to the White House’s statements about acetaminophen,
the Food and Drug Administration published a notice to the Federal Register
approving a form of Leucovorin as a possible treatment for autism, according to
a piece
published by Reuters.
Lee was asked about this and responded that it’s
“premature.”
The drug, according
to the Mayo Clinic, “acts the same way in the body as folic acid” and is
currently used to offset the “harmful effects of methotrexate (a cancer
medicine).”
Lee stated that folic acid “affects neurodevelopment.” The
challenge with “promoting Leucovorin at this time is that the existing
evidence” for the drug alleviating symptoms associated with autism “is
remarkably premature. There’s only been a handful of very small studies which
have some methodological issues. … In short, more research is needed.”
Stand-alone Study?
Research exploring links between acetaminophen and autism
are still fairly new. According to Lee, the studies tend to fall into two large
camps.
Studies that engage in “sibling control analysis,” as Lee’s
and others’ have done, are showing an emerging “consensus … that for the
studies that are actually controlling for genetics and familial confounding,
those studies are not supporting that a causal association exists between
acetaminophen use and autism.”
On the other hand, Lee said, “the sort of apples to oranges
studies just looking at folks who use [acetaminophen] versus folks who don’t
use,” Lee said, “they’re finding the small increase in risk.”
Talk with Your Physician
As with any treatment, patients need to talk with their
physician about the best treatment course for them.
Lee noted, for example, that “fevers are a known quantity as
far as potential adverse effects” on a developing fetus. “Certainly the
evidence base for fevers being harmful,” he continued, “is a lot stronger in my
opinion, than for acetaminophen being harmful. At least at recommended doses.”
However, he also stressed that he is not a clinician and
that “this is one of those areas where you should talk to your doctor.”
Potential Sidebar
Tylenol and Autism: What Moms Should Know
👩👧 Why this
is in the news
The White House recently suggested Tylenol (acetaminophen) during pregnancy
might be linked to autism. That raised a lot of questions for moms.
🩺 What doctors say
- The
Society for Maternal-Fetal Medicine says Tylenol has not been proven
to cause autism. - A
study of 2.4 million children in Sweden found no added risk when
researchers compared brothers and sisters — one exposed to Tylenol in the
womb, the other not.
🍎 Apples to oranges
vs. apples to apples
- Moms
who take Tylenol are often already sick, which can affect outcomes. - Autism
also has strong genetic roots. Looking at siblings (apples to apples)
shows Tylenol isn’t causing autism.
💊 Other treatments?
A drug called Leucovorin has gotten attention, but experts say it’s too
early to know if it helps.
👩⚕️ Bottom line for
moms
- Fevers
can harm a developing baby. Tylenol is one of the safest ways to bring
down a fever. - Always
follow your doctor’s advice for medication during pregnancy. - Don’t
rely on headlines or social media for medical decisions.
👤 Author Biography:
Martin Davis
Martin Davis is the editor of the FXBG Advance, where
he focuses on bringing clarity, context, and depth to complex issues that shape
the Fredericksburg region and beyond. With a background in faith, culture, and
public policy reporting, Davis has spent more than two decades helping readers
cut through noise and understand the stories that matter most. His work blends
careful research with accessible storytelling, always grounded in accuracy and
fairness.
📰 About the FXBG Advance
The FXBG Advance is Fredericksburg Parent and Family
Magazine’s sister publication, created to deliver deep, trustworthy, and
analytical local journalism. While Fred Parent equips families with
resources for day-to-day living, the Advance digs into the region’s most
pressing civic, cultural, and policy issues — giving readers thoughtful
reporting they can rely on.
From unpacking complicated research to analyzing local
decision-making, the Advance works to ensure the Fredericksburg
community has access to journalism that is clear, independent, and rooted in
facts.
🔗 Read more at FXBG
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