- A new 20-year study is the latest to show no causal link between acetaminophen (Tylenol) use during pregnancy and a risk of autism or attention deficit hyperactivity disorder (ADHD).
- The growing evidence contradicts the Trump administration’s stance on the safety of Tylenol use during pregnancy.
- Using Tylenol for pain relief during pregnancy is widely regarded as safe, but any concerns can be discussed with your doctor.
A new 20-year study out of Hong Kong is the latest research to show no causal link between acetaminophen use during pregnancy and an increased risk of autism or attention deficit hyperactivity disorder (ADHD).
These findings were published on June 29 in
The researchers found that the lack of association between Tylenol use during pregnancy and neurodevelopmental disorders was consistent. The findings were upheld regardless of the trimester in which Tylenol was prescribed or the dose and frequency of use.
In September 2025, the Trump administration suggested that taking Tylenol during pregnancy may raise the risk of autism in children.
The
This study adds to the growing body of evidence showing no link between using acetaminophen, also known as paracetamol, during pregnancy and neurodevelopmental disorders in children.
For instance, a recent
“The exaggerated hype and misrepresentation about acetaminophen [Tylenol] increasing the risk of autism and ADHD during pregnancy has been exploited, harmful to pregnant women, and causing unnecessary confusion,” Sherry Ross, MD, board certified OB-GYN and Women’s Health Expert at Providence Saint John’s Health Center in Santa Monica, CA, told Healthline. Ross wasn’t involved in the study.
A number of high quality studies have recently examined Tylenol use during pregnancy and found no link to autism, ADHD, and other brain disorders. Here’s a closer look.
Gold-standard review of sibling comparison studies
A systematic review and meta-analysis found no evidence to suggest that using acetaminophen during pregnancy raises the risk of neurodevelopmental disorders like autism, ADHD, or intellectual disabilities.
The results, originally published in January, appear in
The Lancet review examined 43 existing studies that had the highest quality and most rigorous research methods.
These studies compared pregnancies where the individual had taken acetaminophen (Tylenol) to pregnancies where the individual had not taken the medication.
They then pooled the results of sibling-comparison studies in which siblings born to the same mother were compared: one pregnancy included acetaminophen exposure, and the other didn’t. This helped control for genetic, family-environmental, and long-term parental characteristics that traditional studies have not accounted for.
The sibling-comparison studies included 262,852 children assessed for autism, 335,255 for ADHD, and 406,681 for intellectual disability. It was confirmed that taking acetaminophen in pregnancy was not linked to childhood autism, ADHD, or intellectual disability when compared to pregnancies with no acetaminophen exposure.
“Our findings suggest that previously reported links are likely to be explained by genetic predisposition or other maternal factors such as fever or underlying pain, rather than a direct effect of the paracetamol (acetaminophen) itself,” Asma Khalil, professor of obstetrics and maternal fetal medicine at City St George’s, University of London and Consultant Obstetrician, who led the study, said in a press release.
“The message is clear — paracetamol remains a safe option during pregnancy when taken as guided,” she added.
Ross agreed. “Tylenol is commonly used to treat fever, headache, and pain during pregnancy,” she said.
“It is safe to use in pregnancy for these common and potentially dangerous conditions. These frequent complaints during pregnancy are safely treated using Tylenol with minimal risks. The risks of untreated fevers, headaches, and pain during pregnancy may be dangerous for mother and baby and do outweigh the unsupported risks of using Tylenol to treat these harmful symptoms,” Ross continued.
A large review of systematic reviews
An umbrella review of systematic reviews published in
The researchers of this review noted that previous studies, which suggested a slight association between acetaminophen use during pregnancy and autism and ADHD, were flawed.
“Existing evidence does not clearly link maternal [Tylenol] use during pregnancy with autism or ADHD in offspring,” the researchers wrote.
This review was published just months after the U.S. government announcement regarding the risk of using Tylenol during pregnancy and showed there was not sufficient evidence to support this announcement.
Despite the latest research findings, federal health officials upheld their position on the possible risks.
In a statement shared with Healthline, the Department of Health and Human Services (HHS) said that experts have expressed concern about the use of acetaminophen during pregnancy.
Regarding the Lancet review, HHS told Healthline that the authors engineered a finding rather than evaluating causality.
Federal health officials cited Andrea Baccarelli, MD, the Dean of the Harvard School of Public Health, who, according to HHS, has suggested a causal relationship between prenatal acetaminophen use and the neurodevelopmental disorders of ADHD and ASD, as well as related symptomology.
Here’s what you need to know about the current evidence on acetaminophen use during pregnancy and the risk of neurodevelopmental disorders.
Autism spectrum disorder (ASD) is believed to be caused by a combination of genetic and environmental influences. However, the exact cause is still currently unknown.
The exact cause(s) of autism is still to be determined,” Ross said. “Credible medical studies suggest autism is thought to be due to genetic and environmental factors. What is known about the cause of autism is [that] it results from a combination of influences.”
“Autism has a strong genetic influence based on mutations of certain genes that impact brain development. Abnormal wiring of the brain in the early development of the baby is also thought to contribute to the case of autism. Maternal infections, exposure to toxins, and pregnancy and delivery complications are potential environmental factors,” Ross continued.
According to the
Some genetic factors that may influence the development and diagnosis of ASD include:
- certain genetic conditions, such as Down syndrome, fragile X, and Rett syndrome
- a sibling or twin with autism
- older parents
While progress has been made in understanding environmental factors, they alone are unlikely to cause ASD. Rather, they may be more likely to increase the risk of development when combined with genetic factors.
Environmental factors may include:
- advanced parental age at the time of conception
- prenatal exposure to certain pesticides and air pollution
- maternal obesity, diabetes, or immune system disorders
- extreme prematurity or very low birth weight
- any difficulty during birth that may lead to periods of oxygen deprivation in the baby’s brain
Research into the exact causes of autism is ongoing. With early intervention and support, many autistic individuals can still lead a fulfilling life.