Paracetamol in Pregnancy Tied to Heightened ADHD and Autism Risk

A comprehensive analysis has revealed that prenatal exposure to acetaminophen—more commonly known as paracetamol—might elevate the likelihood of children developing neurodevelopmental disorders such as autism spectrum disorder and attention‑deficit/hyperactivity disorder. The findings arise from a landmark review led by the Icahn School of Medicine at Mount Sinai in conjunction with other prestigious institutions, including Harvard T. H. Chan School of Public Health, and draw upon data from 46 studies encompassing more than 100,000 participants.

The research, featured in BMC Environmental Health and employing the Navigation Guide systematic review framework, pinpointed a clear pattern: higher‑quality studies—using biomarker validation and rigorous adjustments for confounders—were consistently more likely to show an association between prenatal paracetamol use and later diagnoses of ASD and ADHD. Mount Sinai’s Dr Diddier Prada highlighted that, given how commonly this drug is used during pregnancy, even marginal increases in risk carry significant public health weight.

Further supporting these findings are analyses from large-scale cohorts. A Swedish nationwide sibling‑control study published in April 2024, involving nearly 2.5 million children, initially found marginally elevated risks of autism, ADHD, and intellectual disability among those exposed to acetaminophen in utero. However, these associations vanished when comparing outcomes among siblings—suggesting that familial factors, rather than the medication itself, may account for the apparent links.

Adding nuance, a US study evaluating prenatal blood biomarkers of acetaminophen found that children whose mothers had detectable levels of the drug in the womb were over three times more likely to receive an ADHD diagnosis. Alarmingly, the risk appeared especially elevated for girls, who were six times more likely to be diagnosed compared with unexposed peers. These findings closely mirror earlier concerns raised in 2025 about ADHD rates being significantly higher among children whose mothers took paracetamol during pregnancy.

Mechanistically, paracetamol’s ability to cross the placental barrier may trigger oxidative stress, hormone disruption, or epigenetic alterations—pathways potentially contributing to atypical fetal brain development.

Given the mixed and evolving evidence, medical experts stress that paracetamol should only be used during pregnancy when truly necessary, at the lowest effective dose and for the shortest duration feasible, and always under medical supervision. Importantly, untreated fever or pain itself can pose risks to both the expectant parent and fetus, underscoring the importance of professional guidance for managing symptoms safely.

Though evidence from high‑quality observational studies suggests a link, conflicting results—particularly from sibling‑control designs—indicate that definitive causal claims remain premature. Further research is urgently needed to resolve these disparities, refine clinical guidance, and explore safer therapeutic alternatives for managing pregnancy‑related discomfort.

The issue carries high stakes: with growing global diagnoses of ASD and ADHD and paracetamol being the most widely used over‑the‑counter drug in pregnancy, even a small risk could translate into meaningful public health consequences.

Now, medical guidelines face mounting pressure to reflect these emerging concerns. Health policy bodies, clinicians, and pregnant individuals themselves must weigh the therapy’s benefits against potential developmental risks, guided by evolving evidence and individual circumstances—not blanket assumptions.