Swedish Study Confirms No Autism Risk from Acetaminophen Use in Pregnancy

Among siblings, researchers say there is no evidence that using acetaminophen during pregnancy increases the risk of autism or ADHD. damircudic/iStockphoto/Getty Images

The situation around the use of acetaminophen (paracetamol) during pregnancy drew the attention of global communities after statements by some politicians about a possible increased risk of autism. While some remarks brought the topic closer to myths, modern scientific data clearly indicate no increased risk. Our study, which covered nearly 2.5 million births in Sweden and was published in 2024, did not confirm a link between acetaminophen use during pregnancy and autism in the child. This is one of the largest such analyses in global practice to date.

To assess risk as objectively as possible, researchers turned to Sweden’s national health registers – among the most comprehensive data sources in the world. The study included about 2.5 million children born between 1995 and 2019 and followed them for up to 26 years.

“Enduring this,” as the president proposed, is not a risk-free option.

Key findings of the study and their implications

During the analysis of acetaminophen use, data were collected from prescriptions and consultations during prenatal visits: about 7.5% of pregnant women reported taking the medication. At the same time, control measures were applied for factors that could influence the results – notably fever and pain – to ensure a fair comparison between groups.

Within the study, researchers examined children’s neurodevelopment, particularly diagnoses of autism, attention-deficit/hyperactivity disorder (ADHD), and intellectual developmental disorders. A distinctive feature of the design was the comparison of siblings: more than 45,000 pairs in which one child was diagnosed with autism and the other was not. Such a comparison helps separate the effect of the medication from genetic or familial factors.

In the general population, there was a trend observed in prior work: children of mothers who reported using acetaminophen during pregnancy appeared to have a somewhat higher risk of autism, ADHD, or intellectual disabilities. However, after comparing siblings with a close age gap, where one child was exposed to the medication and the other was not, this association disappears. Similar findings are supported by studies from Japan, where the context of use also differed, but the result remained the same – there is no increased risk due to sibling analysis.

These data reflect a shift in views on early studies, which often relied on less complete data and did not account for genetic differences. If long-term use of acetaminophen is needed during pregnancy, decisions should be made jointly with a doctor or midwife. At the same time, modern data do not support the claim that taking acetaminophen during pregnancy causes autism.

Agreeing with the recommendations of leading medical organizations, it should be noted: acetaminophen should be used as a safe analgesic and fever-reducing medication during pregnancy in the minimal effective doses and only as needed. Panic and undertreatment of pain or fever during pregnancy can harm both mother and child. If there is a need for prolonged use of the medication – be sure to consult with a doctor or midwife.