- Acetaminophen (Tylenol), also referred to as paracetamol, is an over-the-counter medication that is widely used to treat pain and fevers worldwide.
- However, in September 2025, the United States Government warned of a link between acetaminophen use in pregnancy and autism.
- Now, a wide ranging meta-analysis of high quality studies has found no evidence that taking paracetamol as directed during pregnancy increases the risk of autism, ADHD, or intellectual disability in children.
- Experts from many countries agree that the findings should reassure pregnant individuals that, when used as directed, paracetamol is the safest painkiller for them to use during pregnancy.
Acetaminophen, or paracetamol, commonly sold under the brand name Tylenol in the United States — is a medication used worldwide for the treatment of pain and fevers.
In the United Kingdom alone, around 6,300 tonnes of paracetamol are sold each year, enough for 70 tablets per person annually.
No surprise, then, that the US Government statement in September 2025 that children born to people who used acetaminophen in pregnancy had an increased risk of autism and similar conditions caused widespread concern.
“From an obstetric standpoint, this is a reassuring and methodologically strong study which essentially addressed major limitations of earlier work: biases towards existing genetics, family environment, and the underlying reasons paracetamol is used — such as infection, fever, or pain,“ Anand Singh, MD, a consultant gynecologist and obstetrician at the Cadogan Clinic in London, U.K., who was not involved in this review, told Medical News Today.
“The absence of an association between antenatal paracetamol exposure and autism spectrum disorder, ADHD, or intellectual disability across these high-quality analyses strongly suggests that previously reported links were not causal. This aligns with what many clinicians have observed in practice and with the conclusions of large national registry studies.”
– Anand Singh, MD
The review, conducted by researchers in four different countries, searched numerous databases for studies into the risk of autism spectrum disorder, ADHD, and intellectual disability.
Studies were included if they:
- had a cohort design
- published available information on acetaminophen exposure among pregnant women — from biomarkers, medical records, or self-reported
- had an explicit definition of the primary and, if applicable, secondary, outcomes, diagnosed using validated questionnaires or medical records
- compared pregnancy outcomes in individuals taking paracetamol during pregnancy versus those who did not
- gave information on underlying comorbidities and pharmacological treatments before or during pregnancy
- were sibling-comparison studies, to reduce potential confounders by addressing shared familial factors, such as parental genetics, socioeconomic status, and home environment
- measured one or more of three outcomes — autism spectrum disorder, ADHD, intellectual disability.
In the strongest studies — sibling comparison studies, those at low risk of bias, those with adjusted estimates and those with a follow-up longer than 5 years — the researchers found no association between paracetamol intake during pregnancy and autism spectrum disorder or intellectual disability.
Jagdish Khubchandani, PhD, a professor of public health at New Mexico State University, not involved in the review, told MNT that its findings provided “robust evidence”.
“The review negates a lot of discussion from late fall 2025 on social media and otherwise where paracetamol consumed by pregnant women was linked with neurodevelopmental disorders among children. This review has rigorous methods, a larger number of individual studies included, uses strong rating systems for individual studies, and analyzed all existing studies in multiple ways,” said Khubchandani.
The review authors acknowledge that explaining “the potential causal relationship between paracetamol and conditions such as autism, ADHD, or intellectual disability is challenging.”
However, they state that earlier meta-analyses that suggested a link were “characterised by high heterogeneity and by reliance on conventional observational designs susceptible to residual confounding.”
“By contrast,” they conclude, “the largest and most methodologically rigorous studies provide strong evidence against a causal link.”
An HHS spokesman emphasized the Department’s stance, noting that “many experts have expressed concern of the use of acetaminophen during pregnancy.”
The spokesperson cited Andrea Baccarelli, MD, the Dean of the Harvard School of Public Health, who, according to HHS, argued there was “a causal relationship between prenatal acetaminophen use and the NDDs [neurodevelopmental disorders] of ADHD and ASD [autism spectrum disorder] and the related symptomology.”
At the same time, other experts have expressed the view that these review findings should reassure expecting parents.
“Expectant mothers should be reassured,“ Singh told us. “This study provides strong evidence that paracetamol, when used as directed by clinicians (physicians, midwives and obstetricians) does not increase the risk of major neurodevelopmental conditions.“
Both Singh and Khubchandani highlighted the dangers of untreated fever during pregnancy. Khubchandani told MNT:
“Pregnant women must consider the risks and benefits of untreated fever vs. treatment with paracetamol. There is plenty of evidence to show that untreated fevers in pregnancy can be dangerous for both the mother and baby (e.g. miscarriages, congenital defects, and neurodevelopmental disorders, just to name a few).”
Singh added: “Paracetamol is one of the most commonly used medications in pregnancy worldwide, and fear-driven avoidance — fuelled by headlines rather than evidence — can lead to real harm. Untreated maternal fever and significant pain are well-established risks to both mother and fetus.“
“Clear communication of robust evidence helps counter anxiety, restores trust in evidence-based guidance, and supports informed decision-making,” he told us.
Sylvia Baker, MRCpsych, a consultant psychiatrist specialized in autism and ADHD at Re:Cognition Health, who was likewise not involved in this review, emphasized that autism is a complex, multifactorial condition.
“Autism is not caused by one single factor. The strongest evidence is for a significant genetic contribution, which is why autistic traits and neurodevelopmental conditions often run in families. Other factors linked with increased likelihood include certain genetic syndromes, prematurity, and some pregnancy or perinatal complications. In many cases there is no single identifiable cause.”
“This paper is helpful because it reduces unnecessary anxiety for families and keeps the focus on what matters most clinically [in autism diagnosis]: Early recognition and appropriate support,” she concluded.