New Research Links Prenatal Acetaminophen Exposure to ADHD Risk

Recent research published by the University of Washington in Nature Mental Health (March 2025) has brought renewed attention to the potential risks associated with acetaminophen (Tylenol) use during pregnancy. This study suggests a significant association between prenatal exposure to acetaminophen and an increased likelihood of attention deficit hyperactivity disorder (ADHD) in children. Given that acetaminophen is widely regarded as a safe pain reliever during pregnancy, these findings warrant careful consideration by healthcare professionals and expectant mothers alike.

The study analyzed blood samples from 307 pregnant women during their second trimester to detect biomarkers indicative of acetaminophen use. The children of these women were subsequently monitored for up to 10 years to assess neurodevelopmental outcomes. The results revealed that children whose mothers had acetaminophen biomarkers in their blood were 3.15 times more likely to be diagnosed with ADHD compared to those whose mothers did not have detectable levels of the drug. Specifically, 18% of children exposed prenatally to acetaminophen were diagnosed with ADHD, versus 9% of those unexposed. The association appeared particularly pronounced in female offspring, who were six times more likely to develop ADHD if their mothers used acetaminophen during pregnancy. 

What’s especially interesting about the study is its focus on the placenta—the organ that connects mother and baby. The researchers looked at gene expression in the placenta and found that acetaminophen exposure was linked with changes in genes involved in brain development, inflammation, and how the body handles stress at the cellular level. These changes could be part of the reason why some children exposed to acetaminophen in utero may be more vulnerable to developing ADHD.

How is this article helpful?

For clinicians, this research is a reminder of how intertwined physical and mental health truly are. When working with children who have ADHD—or their families—it’s helpful to understand the wide range of biological and environmental factors that contribute to the condition. For patients, especially those who are pregnant or planning to become pregnant, this is not a call for panic but for informed conversations with healthcare providers about the risks and benefits of all medications, even over-the-counter ones.

This article can also be meaningful for adults with ADHD—especially those who are seeking to understand why they struggle with focus, organization, or impulsivity despite their best efforts. For many, ADHD is a condition that has shaped their lives long before it was formally diagnosed, and understanding potential prenatal influences, like exposure to acetaminophen, can provide context that feels validating rather than stigmatizing. It reinforces the idea that ADHD is not simply a result of poor choices, laziness, or lack of willpower, but a neurodevelopmental condition potentially shaped by early biological factors outside their control.

Knowing that ADHD has roots as early as in utero may also encourage greater self-compassion, acceptance, and willingness to engage in treatment—whether that includes therapy, medication, lifestyle changes, or support groups.

In the end, this study doesn’t offer simple answers, but it does raise awareness about a potential risk that many people haven’t considered. As providers and patients, we can all benefit from staying informed and working collaboratively to make the safest choices possible during pregnancy—choices that may have long-lasting impacts on a child’s development and well-being.

One last thought

This article can serve as a valuable tool for clinicians when discussing ADHD with patients and families by reinforcing the message that ADHD is a complex condition with multiple contributing factors—biological, genetic, and environmental. Understanding that prenatal exposures, like acetaminophen, may play a role can help shift the conversation away from parent-blaming and toward a more informed, compassionate, and evidence-based framework. For therapists and other prescribing providers, these findings can support psychoeducation efforts, guide clinical histories (including prenatal exposures), and inform early intervention planning. By staying up to date on emerging research, we can better support families in understanding their child’s condition and empower them to engage actively in care decisions.

Find research article here.