Tylenol and Autism
If you’ve been following the news lately, you may have seen reports of lawsuits being filed against the makers of Tylenol and other acetaminophen-containing products. The basis for these lawsuits is new scientific research suggesting the use of acetaminophen during pregnancy may increase the risk of having a baby with autism. In this blog post, we’ll take a look at the science behind these claims and what you need to know if you’re considering taking acetaminophen during pregnancy.
The Science Behind the Claims
The research linking acetaminophen use during pregnancy to autism risk is relatively new. The first study to report an association was published in 2014. Since then, several more studies have been published, but it’s important to keep in mind that all of these studies are observational in nature. This means they can only show an association between acetaminophen use and autism risk; they cannot prove that acetaminophen use causes autism.
It’s also important to note that the magnitude of the risk reported in these studies is relatively small. For example, one study found that women who took acetaminophen for more than 20 weeks during pregnancy were 1.5 times more likely to have a child with autism than women who did not take acetaminophen. Another study found that pregnant women who took acetaminophen for more than 28 days had a slightly increased risk of having a child with autism.
So, what do these findings mean? Should you avoid taking acetaminophen during pregnancy? It’s important to remember that even though the risk of having a child with autism may be slightly increased with acetaminophen use, the absolute risk is still very low. For example, if the base rate of autism is 1%, then the risk would increase to 1.5% with acetaminophen use (i.e., from 1 in 100 babies to 1 in 67 babies).
Additionally, it’s important to consider the risks associated with not taking acetaminophen during pregnancy. Acetaminophen is often used to relieve pain and fever during pregnancy, and there are risks associated with both pain and fever during pregnancy. Therefore, it’s important to talk to your doctor about whether or not the benefits of taking acetaminophen during pregnancy outweigh the potential risks.
The bottom line is that while there may be a small increased risk of having a child with autism if you take acetaminophen during pregnancy, the absolute risk is still very low. Additionally, there are risks associated with both pain and fever during pregnancy, so it’s important to talk to your doctor about whether or not the benefits of taking acetaminophen during pregnancy outweigh the potential risks.
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3) Li DK et al. Maternal mid-pregnancy paracetamol use in relation to child neurodevelopmental outcomes at age 3 years . Br J Obstet Gynaecol 2015; 122: 933-40.
4) Meijer L et al. Maternal paracetamol use around conception associated with increased ASD symptoms . Autism Res 2016; 9: 330-8.
5) American College of Obstetricians and Gynecologists (ACOG). ACOG Practice Bulletin No 134: Fever During Pregnancy . Obstet Gynecol 2013; 122: 416-22..
6) Stotland N et al.. Association Between Maternal Fever During Pregnancy and Autism Spectrum Disorder . JAMA Psychiatry 2017; 74: 400-7..