No proven link between acetaminophen during pregnancy and autism, officials say

Health authorities on Wednesday reiterated that acetaminophen, known as paracetamol in many countries, remains the recommended first-line pain and fever relief for pregnant people and that there is no proven causal link to autism. The clarification comes amid public comments from former U.S. President Donald Trump, who claimed there is a link between the drug and autism and urged pregnant women to avoid it except in extreme cases such as high fevers.

Trump has said the drug “is no good” and that women should “fight like hell” to limit its use during pregnancy. Medical bodies, including major obstetric and pediatric groups, say the drug is safe when used as directed and remains the best available treatment for pain and fever during pregnancy. Health officials stressed that high fever itself can pose risks to a developing fetus and that untreated discomfort is not advised.

Autism is a lifelong neurodevelopmental condition that presents on a spectrum. It affects how people perceive and interact with the world, with a wide range of characteristics. Some autistic people require substantial support, while others have strong abilities but may struggle with social interaction or communication. Autism is not a learning disability or a mental health condition. The UK National Autistic Society notes that about a third of autistic people also have a learning disability, and mental health problems are more common in the autistic population. There is no blood test or brain scan to diagnose autism; clinicians rely on behavioral observations and developmental history rather than a single biomarker.

The prevalence of autism diagnoses has risen in many countries. In the United States, about 1 in 31 children were identified with autism in 2022, up from about 1 in 149 in 2000. Among eight-year-old boys the rate is higher than for girls. In the United Kingdom, a 2023 Lancet study found that about 1 in 34 children aged 10 to 14 were diagnosed with autism in 2018. Across countries, comparisons are difficult because diagnostic criteria, awareness, access to healthcare and cultural factors vary. A 2022 review of 71 studies estimated an average global prevalence near 1%, with substantial variation—from well under 1% in some low-income settings to nearly 4% in parts of Australia.

Rates have climbed largely because of greater recognition and broadened definitions rather than a simple rise in cases. In the United States, the Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria broadened in 2013 to include what had been labeled Asperger’s Syndrome under autism spectrum disorder, a change mirrored in several other countries. Data from the UK show an eight-fold rise in new diagnoses between 1998 and 2018 when consistent criteria were used. Some critics, including former U.S. Health Secretary Robert Kennedy Jr., have questioned whether rising rates reflect epigenetic or environmental factors rather than diagnostic expansion, though mainstream researchers stress that no single cause has been identified.

There is no scientific evidence that acetaminophen causes autism. Trump’s remarks have surprised many medical professionals, who emphasize that paracetamol/acetaminophen remains the standard treatment for pain and fever during pregnancy. Researchers say it is difficult to isolate the effect of a single exposure—such as acetaminophen—from a web of potential influences including parental health, genetics, and environment. Some research groups have reported associations between acetaminophen use during pregnancy and neurodevelopmental outcomes, but findings are mixed, and many studies acknowledge limitations.

In August, a review led by researchers at Icahn School of Medicine at Mount Sinai analyzed 46 older studies. Of those, 27 reported a link between acetaminophen use and increased risk of neurodevelopmental disorders including autism and ADHD, nine showed no significant association, and four suggested a protective effect. The authors cautioned that more work is needed and recommended cautious, time-limited use of acetaminophen during pregnancy. By contrast, a 2024 study of 2.5 million Swedish births comparing autistic children with their siblings—designed to account for genetic factors—found no evidence of a causal link between autism and acetaminophen exposure. A 2025 Japanese study of siblings reported a small increased risk that could partly reflect misclassification or other biases, rather than a definitive causal effect. The Autism Science Foundation notes that, based on current data, there is not enough evidence to support a link between Tylenol and autism, though it advises caution and medical consultation during pregnancy. Tylenol’s maker, Kenvue, has stated that scientific evidence clearly shows acetaminophen does not cause autism.

What to know about pain relief in pregnancy remains consistent across major medical bodies. Acetaminophen is widely recommended as the first-choice medication for pain and fever during pregnancy by groups such as the American College of Obstetricians and Gynecologists and the Royal College of Obstetricians and Gynaecologists. They emphasize that high fevers in early pregnancy can be linked to miscarriage, preterm birth or neural tube defects, and that acetaminophen, used at recommended doses, is considered safer than alternatives in many situations. Ibuprofen is generally avoided during pregnancy unless prescribed by a clinician, particularly after the 20th week, due to potential effects on fetal circulation and kidney function. The general population should still use acetaminophen at the lowest effective dose and for the shortest duration to minimize overdose risk.

For adults, NHS guidance notes typical dosing as one or two 500 mg tablets at a time, up to four times in 24 hours, with a maximum daily total of about 4,000 mg. The NHS also notes that acetaminophen is the recommended first-choice pain reliever for breastfeeding mothers. Pregnant individuals should seek medical advice if pain or fever persists, if there are concerns about dosing, or if other medications are being used concurrently.

Separately, health officials also touched on folic acid, sometimes called folate, during pregnancy and research into potential adjunct therapies. Folate plays a key role in fetal development, and some studies have linked adequate folate levels with a lower risk of neural tube defects and, in some studies, a reduced risk of autism. Studies from Norway, the United States and Israel reported a 30–70% lower likelihood of autism among mothers who took folic acid around conception, though results have not been entirely consistent across all research. Leucovorin, a form of folinic acid used in some cancer therapies to mitigate side effects, has also been explored in very early-stage trials for autism. Trials have shown some small improvements in certain language or communication metrics in autistic children, but researchers caution that evidence is preliminary and not sufficient to support routine use for autism.

In summary, major health authorities maintain that acetaminophen remains the recommended and generally safe option for pain and fever during pregnancy when used as directed. Ongoing research continues to investigate how genetics, environment and various exposures may influence autism risk, but no conclusive cause-and-effect link to acetaminophen has been established. Expectant parents should consult their healthcare providers about appropriate medication use, especially during pregnancy, and avoid self-prescribing when there are concerns about fetal health. The scientific community continues to stress cautious interpretation of observational findings and the importance of evidence from well-designed studies before drawing firm conclusions.

Experts say the safest course for pregnant individuals is to follow medical guidance and use medications only as recommended by doctors. While the conversation about autism prevalence and its causes will understandably continue, the current consensus remains that acetaminophen, when used appropriately, does not cause autism and should be managed under clinical supervision, particularly when fever or pain is present. Researchers and advocacy groups alike emphasize the need for cautious interpretation of early findings and continued funding for high-quality studies to better understand autism and its risk factors. In the meantime, expectant families should maintain regular prenatal care, discuss any medications with a healthcare professional, and remain attentive to signs that warrant medical evaluation.