The FDA updates acetaminophen warnings for pregnant women and approves leucovorin for treating cerebral folate deficiency.
On September 22, 2025, the US Food and Drug Administration (FDA) issued a pair of announcements with immediate implications for women's health.
The FDA announced the initiation of a label change for acetaminophen (Tylenol and similar products), reflecting data that prenatal exposure may be associated with increased risk of neurodevelopmental disorders.1
The agency also approved leucovorin calcium (Wellcovorin) for the treatment of cerebral folate deficiency (CFD), a rare neurological condition with manifestations that include autistic features, seizures, and movement difficulties.2
Acetaminophen remains the most commonly used over-the-counter analgesic and antipyretic in pregnancy. The FDA cited multiple large-scale studies, including the Nurses’ Health Study II and the Boston Birth Cohort, showing an association between maternal acetaminophen use and later diagnoses of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD).¹ The strongest associations were observed with prolonged, chronic use across gestation.1
In an official statement,noted: *“The precautionary principle may lead many to avoid using acetaminophen during pregnancy, especially since most low-grade fevers do not require treatment. It remains reasonable, however, for pregnant women to use acetaminophen in certain scenarios," said Marty Makary, MD, MPH, commissioner of the FDA.
Although causality has not been established, the agency emphasized the importance of clinician awareness and shared decision-making. Untreated maternal fever itself has been linked with adverse outcomes, underscoring the need to weigh potential risks of both the drug and the condition being treated. Importantly, acetaminophen remains the only over-the-counter antipyretic approved for use in pregnancy, as aspirin and nonsteroidal anti-inflammatory drugs have well-documented adverse fetal effects.1
In parallel, the FDA approved leucovorin calcium for CFD after reviewing mechanistic studies and case reports published between 2009 and 2024.² This condition, characterized by impaired folate transport into the central nervous system, can present with developmental delay, seizures, and behavioral phenotypes consistent with ASD.2
“The FDA is collaborating with GSK to broaden the existing Wellcovorin label. This effort reflects the FDA’s commitment to identify opportunities to repurpose drugs to treat chronic diseases. The FDA remains committed to finding and treating the root causes of autism," Tidmarsh, MD, PhD, director of the FDA’s Center for Drug Evaluation and Research, stated
For obstetrician–gynecologists, the FDA’s announcement reinforces the need for clear counseling around acetaminophen use in pregnancy. Patients should be advised that:
Regarding CFD, although this approval has no direct impact on obstetric prescribing, the growing recognition of neurodevelopmental disorders linked to prenatal and early-life exposures underscores the importance of maternal health optimization and interprofessional collaboration with pediatricians and neurologists.
The FDA’s dual actions highlight an ongoing shift toward both risk mitigation in pregnancy and expanded treatment options for pediatric neurological conditions. For OB/GYNs, these developments reinforce the need for evidence-based counseling on acetaminophen use and awareness of evolving therapies for conditions contributing to the rising prevalence of ASD.
Editor's Note: Artificial Intelligence was used in the creation of this content.
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