Few questions weigh on expecting parents like this one: could a medicine I took during pregnancy affect my child? Over the past year, two very common medicines have been at the centre of that worry: paracetamol (called acetaminophen in North America and sold as Tylenol in the US) and antidepressants. In October 2026, PsyPost covered two new studies on them. Their shared message is reassuring and fairly simple: the stronger the evidence, the weaker the link.
Why the Question Became So Loud
On 22 September 2025, the US Food and Drug Administration (FDA) announced that it was starting the process to change the label of acetaminophen to reflect a possible association with autism and ADHD, and sent a letter to physicians. The same announcement stated that "a causal relationship has not been established". The American College of Obstetricians and Gynecologists (ACOG) said the message was not backed by the full body of evidence, and the next day the European Medicines Agency said there was no new evidence requiring a change to its recommendations. In August 2025, a review in Environmental Health that rated 46 studies without pooling their numbers had concluded that the evidence was consistent with an association. Hence the confusion.
The New Umbrella Review on Paracetamol
A team from the University of Santiago de Compostela in Spain, led by Hoda Tayebi-Hillali, published its work in Developmental Medicine & Child Neurology. Rather than adding one more study, they did an umbrella review: they gathered the existing meta-analyses (searched in six databases up to November 2025) and rated their quality with a standard tool called AMSTAR-2. They found seven meta-analyses covering more than 3 million participants, then pooled them step by step, keeping only better-quality work each time.
- All meta-analyses together: a small association, with a risk ratio of 1.17 for autism and 1.29 for ADHD.
- Only the single meta-analysis rated high quality: 1.10 for autism (not statistically significant) and 1.16 for ADHD.
- Only primary studies at low risk of bias: 1.05 for autism (two large studies, from Sweden and Japan) and 1.17 for ADHD (three studies whose results varied a lot).
Most of the earlier meta-analyses were rated low quality. The authors conclude that the associations are probably influenced by residual confounding and by errors in measuring who took the medicine, that current evidence does not support a robust causal relationship, and that paracetamol remains an appropriate first-line treatment in pregnancy when clinically indicated. As the lead author told PsyPost: "The size of the effect, therefore, does not justify alarm."
To be precise, the link did not vanish in every analysis: small associations remained in some models, especially for ADHD. The review also could not assess dose or timing, and its strongest estimates rest on a handful of studies.
Comparing Siblings: The Swedish Study
One of the strongest studies on the topic was published in JAMA in April 2024. Viktor Ahlqvist, Brian Lee and colleagues at the Karolinska Institutet followed 2,480,797 children born in Sweden between 1995 and 2019. Paracetamol use was recorded during pregnancy, at antenatal visits, not recalled years later. In the usual analysis, exposure was linked to very slightly higher risks (a hazard ratio of 1.05 for autism and 1.07 for ADHD). By age 10, 1.53% of exposed children had an autism diagnosis, compared with 1.33% of unexposed children.
Then the researchers compared siblings: children of the same mother, born from one pregnancy with paracetamol and one without. Siblings share much of their genes and family environment, so this design removes many hidden factors. The link disappeared (hazard ratio 0.98 for both autism and ADHD), with no sign that higher doses meant higher risk.
Antidepressants: What the Welsh Study Found
The second study, published in PLOS Medicine on 29 September 2026 by Saraid McIlvride and colleagues at the University of Glasgow, used linked GP, maternity and school records for 167,447 children born in Wales between 2009 and 2016. Its key idea was to separate the medicine from the illness it treats: 7.6% of the children were exposed to untreated maternal depression, 4.2% to treated depression, and 3.6% to antidepressants without a recorded depression diagnosis.
- Compared with unexposed children, both maternal depression and antidepressants were associated with more autism and ADHD diagnoses.
- But when children of mothers with depression were compared with each other, treated versus untreated, there was no significant difference in autism or ADHD.
- For the broader outcome of special educational needs at school, antidepressants were linked to a small extra absolute risk (2.9 more children per 100 among mothers with depression), which the authors say may partly reflect more severe depression.
The study had no data on how severe the depression was, did not use sibling comparisons, followed children only to an average age of under 6 (before many ADHD diagnoses are made), and covered a mostly White population. The lead author also noted that "untreated depression can have a serious impact on the well-being of both mother and baby".
Why Raw Links Shrink: Confounding
Both stories illustrate the same statistical trap, called confounding: a third factor that is linked both to the medicine and to the child's outcome.
- Confounding by indication. People take paracetamol because of fever, infection or pain, and antidepressants because of depression. The underlying condition, not the medicine, may explain part of the link.
- Genetics. Autism and ADHD are highly heritable, and they share some genetic influences with depression and chronic pain. A parent who carries these traits may be more likely to need medication and also to pass on the genes. Comparing siblings, or treated with untreated mothers, removes much of this effect. Our article on why ADHD and autism diagnoses are rising shows how strongly genetics shape these conditions.
None of this is about what a mother did or did not do. It is about how hard it is to untangle causes in observational data, much like the story we covered in our MMR vaccine fact-check.
What This Means for You
If you are pregnant, do not stop or start a medication in pregnancy without talking to your doctor or midwife: fever and untreated depression carry their own risks. If you are the parent of an autistic child or a child with ADHD, the best current evidence does not show that a painkiller or an antidepressant you took caused it.
And because autism and ADHD run in families, many adults recognise their own traits when a child is diagnosed. If that sounds familiar, our free AQ-10 autism test (10 questions, about 3 minutes) and our ASRS-v1.1 adult ADHD screener (18 questions, about 10 minutes) are a simple first step. The tests on this site are screening tools designed for adults: they are not a diagnosis, but they can help you start a conversation with a professional.
Source: Tayebi-Hillali H, Blanco-Suárez M, Rivas-Mundiña B, Limeres-Posse J, Diniz-Freitas M, Diz-Dios P (University of Santiago de Compostela). Prenatal exposure to paracetamol and the risk of autism and attention-deficit/hyperactivity disorder: An umbrella review and meta-meta-analysis. Developmental Medicine & Child Neurology, published online 23 September 2026, DOI 10.1111/dmcn.70512. Umbrella review of 7 meta-analyses (more than 3 million participants), AMSTAR-2 and ROBINS-E quality ratings. McIlvride S, Rao N, Singh S, Nelson SM, Pell JP, Fleming M (University of Glasgow). Prenatal exposure to maternal depression and antidepressants and neurodevelopmental outcomes: A population cohort study. PLOS Medicine 23(9):e1004658 (2026), DOI 10.1371/journal.pmed.1004658. Population cohort of 167,447 children born in Wales, 2009-2016. Reported by PsyPost, 11 and 13 October 2026. Background: Ahlqvist VH et al. Acetaminophen Use During Pregnancy and Children's Risk of Autism, ADHD, and Intellectual Disability. JAMA 331(14):1205-1214 (2024), DOI 10.1001/jama.2024.3172 (Swedish nationwide cohort, 2,480,797 children, sibling control analysis).