When an Indianapolis mom juggling a fever during pregnancy reaches for Tylenol, she should not face fear-driven headlines. She deserves clear science to make informed choices for her baby.
Parents of children with autism want answers, too. Nationally, about 1 in 31 children are identified with autism, with rates rising over the past two decades. In Indiana, state data show lower rates closer to 1 in 59, though they have also increased over time. So, when a drug as common as Tylenol is linked to autism in the news, fear spreads quickly.
On Sept. 22, the FDA announced it would update acetaminophen’s safety labeling to reflect a “possible association” between prenatal use and later diagnoses of autism and ADHD. The agency emphasized that causation has not been proven and that acetaminophen remains important when clinically indicated.
That same day, President Trump, Robert F. Kennedy Jr. and Health and Human Services leaders described the evidence as “mounting” and suggested the medication might cause autism. Kennedy, a longtime critic of mainstream medicine, amplified the claims, though his arguments lacked peer-reviewed rigor. The framing fueled public concern but drew immediate criticism from medical groups and international bodies.
The World Health Organization stated there is no conclusive evidence that prenatal acetaminophen causes autism. The American College of Obstetricians and Gynecologists cautioned that the medication remains necessary in pregnancy when benefits outweigh risks, and that current studies do not prove causation.
Why Kennedy, FDA and others see risk
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Cord blood biomarker data: A Johns Hopkins–led study in the Boston Birth Cohort measured acetaminophen traces in umbilical cord plasma. Children with higher levels at birth were more likely to be diagnosed with autism or ADHD later. The authors warned against assuming causality.
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Other biomarker studies: Research using meconium samples has linked prenatal acetaminophen exposure to ADHD and changes in brain connectivity. These findings suggest a possible biological link but still fall short of proof.
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Precautionary recommendations: Several scientific commentaries argue for prudent use of acetaminophen in pregnancy. They highlight consistent signals across observational studies and note the global scale of exposure, which magnifies even small potential risks.
Why the science falls short
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Sibling-comparison data: A Swedish study of 2.5 million births found small links in standard analyses, but when researchers compared siblings within the same family, the connections vanished. This suggests genetic or environmental factors, not the drug, explain the findings.
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Regulatory caution: The FDA stressed the signal is associative, not causal. ACOG underscored that untreated maternal fever can harm fetal development, and that acetaminophen often remains the safest option compared with NSAIDs. WHO rejected the claim that Tylenol causes autism outright.
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Legal precedent: In federal multidistrict litigation over Tylenol and autism, a judge excluded plaintiffs’ causation experts 2023 and granted summary judgment for defendants in 2024. While not a scientific ruling, it reflects how the current evidence fails to meet evidentiary thresholds.
Putting the evidence into perspective
Association does not mean causation. When pregnant women take acetaminophen, it is often because they have a fever, an infection or another condition that can affect a baby’s brain development on its own. Biomarker studies help measure exposure more precisely, but they still cannot eliminate other possible explanations. Even when studies show a link, the added risk is very small, usually just a fraction of a percent.
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For Indiana mothers-to-be, the guidance is clear. Talk to your OB-GYN before taking acetaminophen. Keep a log of doses to avoid accidental overuse, especially with combination cold medicines. Acetaminophen remains appropriate for clinically significant pain or fever in pregnancy, since avoiding it altogether may expose mothers and babies to greater risks from untreated illness. Doses should be kept as low as possible and used for the shortest time necessary. Families should also be aware that many cold and flu medicines contain acetaminophen, making label-reading essential.
The bottom line
The FDA’s action signals caution, not condemnation. President Trump’s and Kennedy’s framing leaned further than the science supports, prompting WHO and ACOG to push back. The evidence is mixed: biomarker and observational studies raise concern, but the largest family-controlled study shows no effect.
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In Indiana, where social media often spreads health myths faster than medical updates, it is critical to trust peer-reviewed science over viral claims. Autism remains a profound challenge for families across the Hoosier state. Resources such as the Indiana Resource Center for Autism at IU Bloomington provide essential support but families deserve rigorous science and not political headlines.
Acetaminophen warrants careful study and careful use. What it does not deserve is to become another cultural flashpoint. Headlines can fuel fear but science requires patience. For Indiana parents the message is simple: trust your doctors, track your use, and lean on evidence rather than speculation.
Dr. Raja Ramaswamy is an Indianapolis-based physician and the author of “You Are the New Prescription.”
This article originally appeared on Indianapolis Star: The truth about Tylenol, pregnancy and autism risk for moms | Opinion
