There is currently **no strong evidence directly linking aspirin use during pregnancy to autism spectrum disorder (ASD)** in children. Unlike acetaminophen (paracetamol), which has been studied extensively with mixed and inconclusive results regarding its association with autism, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) have not been shown to cause autism when used during pregnancy according to authoritative sources.
Aspirin is an NSAID with anti-inflammatory and antioxidant properties. Some experimental animal studies suggest aspirin might even have protective effects against autism-like symptoms induced by certain toxins during pregnancy. For example, a 2023 study using a rat model of autism induced by valproic acid (VPA) found that aspirin treatment improved social behavior, cognition, and reduced oxidative stress markers in offspring, suggesting a potential therapeutic role rather than harm from aspirin exposure in pregnancy[2]. However, this is an animal study and does not directly translate to human pregnancy safety or autism risk.
In contrast, acetaminophen (paracetamol), which is commonly used during pregnancy for pain and fever, has been the subject of ongoing debate. Some epidemiological studies have suggested an association between prolonged or chronic acetaminophen use during pregnancy and increased risk of neurodevelopmental disorders including autism and ADHD. However, these findings are inconsistent, and no causal relationship has been established. The FDA recently acknowledged this possible association and is considering label changes to inform physicians and patients, but also emphasizes that acetaminophen remains the safest over-the-counter option for pain and fever in pregnancy compared to aspirin or ibuprofen, which have known fetal risks[3][4][1].
The UK Teratology Information Service and other expert bodies maintain that effective management of maternal pain and fever is important for fetal and maternal health, and paracetamol remains the recommended treatment during pregnancy. NSAIDs like aspirin are generally avoided, especially in later pregnancy, due to risks such as premature closure of the fetal ductus arteriosus and other complications, but these risks are not linked to autism[1].
In summary, while acetaminophen use during pregnancy is under scrutiny for a possible association with autism, **aspirin has not been shown to increase autism risk and may have antioxidant benefits in experimental models**. Nonetheless, aspirin is not routinely recommended during pregnancy due to other fetal risks unrelated to autism. Pregnant women should always consult healthcare providers before using any medication.
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**Sources:**
[1] UK Teratology Information Service, MacDonald Obstetric Medicine Society, British Maternal and Fetal Medicine Society joint statement on paracetamol use in pregnancy and autism, 2025.
[2] PubMed Central: Aspirin’s role in reducing oxidative stress and improving autism-like symptoms in a rat model, 2023.
[3] FDA Notice to Physicians on Acetaminophen Use During Pregnancy, September 2025.
[4] FDA Press Announcement on Possible Association Between Autism and Acetaminophen Use During Pregnancy, 2025.
