# Mechanisms and Modifiers of Prenatal Acetaminophen Exposure and Child Neurodevelopment

> **NIH MH K99** · UNIVERSITY OF WASHINGTON · 2026 · $244,123

## Abstract

PROJECT SUMMARY
Acetaminophen, which is found in more than 600 prescription and non-prescription medications for mild to
moderate pain and fever reduction, is not restricted to pharmacies and is sold over-the-counter in many countries,
including the United States. In most populations worldwide, over 50% of pregnant people report taking
acetaminophen, which easily crosses the placenta and fetal blood brain barrier, potentially affecting fetal brain
development. The United States Food and Drug Administration (FDA) and European Medicines Agency (EMA)
have traditionally viewed acetaminophen as posing minimal risks to the fetus when used as directed but have
called for more rigorous studies and better safety data to inform their recommendations on how pain medicines
are used during pregnancy. Accumulating evidence from epidemiologic and animal research highlights potential
neurodevelopmental risks associated with prenatal acetaminophen exposure, yet limitations remain in the
literature preventing regulatory agencies from assessing whether these associations are causal. Prior studies
could be confounded by genetic or familial factors, and mechanisms linking acetaminophen with adverse
neurodevelopment remain unknown, limiting our ability to develop targets for harm reduction. While adjusting for
a robust set of genetic, environmental, and familial factors, this proposal aims to elucidate molecular mechanisms
and genetic effect modifiers of associations between prenatal acetaminophen and adverse neurodevelopment.
During the mentored K99 phase, I will receive training from leaders in pediatrics, child psychiatry and psychology,
pharmacogenomics, metabolomics, and multi-omics. I will combine this training with my prior expertise in
prenatal acetaminophen research and epidemiology to model associations of maternal blood biomarkers of
acetaminophen with a broad spectrum of child neurodevelopmental outcomes, including ADHD. I will investigate
genotype by prenatal acetaminophen i

## Key facts

- **NIH application ID:** 11229691
- **Project number:** 1K99MH138623-01A1
- **Recipient organization:** UNIVERSITY OF WASHINGTON
- **Principal Investigator:** Brennan H. Baker
- **Activity code:** K99 (R01, R21, SBIR, etc.)
- **Funding institute:** MH
- **Fiscal year:** 2026
- **Award amount:** $244,123
- **Award type:** 1
- **Project period:** 2026-04-01T00:00:00 → 2028-03-31T00:00:00

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/11229691

## Citation

> US National Institutes of Health, RePORTER application 11229691, Mechanisms and Modifiers of Prenatal Acetaminophen Exposure and Child Neurodevelopment (1K99MH138623-01A1). Retrieved via AI Analytics 2026-07-07 from https://api.ai-analytics.org/grant/nih/11229691. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*