Many pregnant women worry about what medicines are safe to take, especially when they have pain or fever.
One of the most commonly used medications during pregnancy is acetaminophen, also known by the brand name Tylenol.
Doctors often recommend it because it has long been considered safer than many other pain relievers.
However, in recent years, public concern has grown after some reports suggested that using this medicine during pregnancy might increase the risk of autism, attention problems, or learning difficulties in children.
A major new study has now provided reassuring news. Researchers from City St George’s, University of London reviewed the best available evidence and found no clear link between acetaminophen use during pregnancy and autism, attention-deficit hyperactivity disorder, or intellectual disability in children.
Their findings were published in a The Lancet Obstetrics, Gynaecology and represent the most thorough analysis on this topic so far.
The research team examined results from 43 previous studies involving hundreds of thousands of children.
Earlier studies had sometimes suggested a small connection between acetaminophen exposure before birth and developmental conditions. However, those studies often had important weaknesses.
For example, some did not fully account for family history or genetic factors, which can strongly influence whether a child develops autism or attention problems. Others relied on incomplete records of medication use or did not consider the reasons why mothers took the medicine in the first place, such as illness or high fever.
To overcome these problems, the new analysis focused on the strongest type of evidence available. One key method involved comparing siblings from the same family. In these cases, one child had been exposed to acetaminophen during pregnancy while another had not.
Because siblings share many genetic traits and grow up in similar environments, this approach helps scientists separate the effects of medication from inherited risks or family circumstances.
The sibling comparison data included more than a million children in total who were evaluated for developmental conditions. Across these large groups, researchers found no evidence that prenatal exposure to acetaminophen increased the likelihood of autism, ADHD, or intellectual disability.
This suggests that earlier warnings were likely influenced by other factors rather than the medicine itself.
Experts believe that mothers who take acetaminophen during pregnancy may already have health conditions that increase risk, such as infections, pain, or fever. Untreated fever, in particular, can be harmful to a developing baby.
Therefore, avoiding medication when it is needed could actually be more dangerous than taking it. This is why doctors have continued to recommend acetaminophen as the first choice for treating pain and fever during pregnancy when used at the correct dose.
The researchers also carefully checked the quality of each study they included to make sure the results were reliable. Even when they focused only on the highest-quality studies, the conclusion remained the same: there was no meaningful increase in risk.
However, they noted that more detailed information is still needed about how timing, dosage, and frequency of use might affect outcomes, as not all studies reported these details.
For pregnant women, these findings provide important reassurance. Managing pain, headaches, or fever is not only about comfort but also about protecting the health of both mother and baby.
Severe pain and high temperature can place stress on the body and may lead to complications if left untreated. Having a medication that is considered safe allows women to address these issues without unnecessary fear.
In reviewing the study’s findings, it is clear that the strongest evidence does not support a harmful effect of acetaminophen on child brain development. The results highlight the importance of high-quality research methods, such as sibling comparisons, in understanding complex health questions.
While no medication should be used without guidance, this analysis suggests that acetaminophen remains a reasonable option during pregnancy when taken as directed by a healthcare professional. Future research may continue to monitor long-term outcomes, but for now, parents and doctors can feel more confident about its safety.
If you care about autism, please read studies that cats may help decrease anxiety for kids with autism and new study may develop better treatment for autism
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