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A massive new study has found a worrying link between a number of common medications taken during pregnancy and a higher risk of autism in children.
Researchers looked at more than six million births in the US and found 15 widely prescribed drugs—antidepressants, heart medications, cholesterol-reducing drugs like statins—increased autism risk if taken during pregnancy.
These drugs account for 400 million prescriptions annually in the US.
Statins had a warning attached to their use during pregnancy until 2021, when it was removed.
The researchers believe the effects observed may have something to do with disruptions to cholesterol-synthesis.
Cholesterol, perhaps the most widely demonised natural substance in modern medicine, is a building block of every single cell in the human body and is critical, in particular, to the development and health of the brain, which contains the most cholesterol of any organ in the body.
A fetus does not begin producing its own cholesterol until about halfway through gestation, meaning disruptions to the mother’s cholesterol-synthesis during the first half of the pregnancy could have disastrous effects on brain development, paving the way for conditions like autism.
Study Finds reports, “Published in Molecular Psychiatry, the study found that exposure to at least one of these cholesterol-disrupting medications during pregnancy was associated with a 47% relative increase in the risk of an autism diagnosis in the child. The more of these drugs a pregnant woman was prescribed at the same time, the higher the risk climbed, reaching more than double the baseline risk when four or more were taken at once.
“Notably, the share of pregnant women prescribed at least one of these medications more than tripled over the study period, rising from 4.6% in 2014 to 16.8% in 2023.”
The fifteen medications were: sertraline, fluoxetine, bupropion, buspirone, aripiprazole, cariprazine, haloperidol, trazodone, metoprolol, propranolol, nebivolol, atorvastatin, simvastatin, rosuvastatin and pravastatin
Almost 700,000 pregnant women, or 11% of the group studied, were prescribed at least one of these medications.
Of the six million children, about 235,000 or 3.8% received an autism diagnosis.
And of the children diagnosed with autism, 15% had a mother who took one or more of these cholesterol-disrupting medications.
Study Finds provides further explanation: “What bolstered the researchers’ case was the pattern they observed when women took multiple medications. Each additional cholesterol-disrupting drug prescribed during pregnancy was associated with a 1.33-fold increase in autism risk. When four or more were prescribed at the same time, the risk reached 2.33 times higher than the baseline. This stacking effect, the team noted, lines up with earlier lab work showing that combining several of these medications further raised levels of a potentially toxic byproduct in pregnant women’s blood.
“The drug tied to the single highest risk was cariprazine, an antipsychotic, which showed a 2.59-fold increased risk of autism after adjusting for other factors. Across all fifteen medications, the strength of the autism association tracked closely with how powerfully each drug had been shown in prior lab studies to block a specific step in cholesterol production.
“To check that the pattern was specific to these cholesterol-disrupting drugs and not just a general effect of taking any medication during pregnancy, the researchers ran the same analysis on six commonly prescribed prenatal medications with no known effect on cholesterol production, including treatments for allergies, constipation, acid reflux, iron deficiency, and nausea. Those medications showed only minimal associations with autism risk, with adjusted risk increases ranging from just 2% to 17%, far below what was seen with the cholesterol-disrupting drugs.”
In September, as promised, Secretary of Health and Human Services Robert F. Kennedy Jr. announced the findings of an investigation into the environmental causes of autism.
Among the causes were Tylenol use during pregnancy and also low levels of folate.
Advance warning of the findings caused shares in Tylenol maker Kenvue to fall sharply. Kenvue has since attempted to lobby the FDA to prevent updated warnings about the risk of using the Tylenol during pregnancy from being included on the medication’s label.
Studies have indicated a link between use of Tylenol during pregnancy and autism / adhd.
Hundreds of lawsuits linking acetaminophen to autism or attention-deficit hyperactivity disorder have been filed; although a federal judge in 2023 ruled that the scientific evidence behind the claims was unreliable.
