New research indicates that certain medications, widely consumed by pregnant women in the United States, might elevate the likelihood of autism in their children.

With autism now affecting roughly one in every 31 children across the nation—a dramatic rise from the one in 150 statistic seen in the early 2000s—scientists are investigating possible contributors. Factors such as improved diagnostic methods, environmental pollution, and pharmaceutical use are under scrutiny.

Researchers in Nebraska have recently focused their attention on prescription drugs that inhibit cholesterol synthesis.

These include statins, as well as other medications grouped under sterol biosynthesis-inhibiting drugs (SBIMs), which also encompass popular antidepressants and beta blockers, typically prescribed for managing anxiety and hypertension.

Although cholesterol accumulation can contribute to heart disease by clogging arteries, it plays a vital role in developing brain cell membranes and facilitating neuron communication through synaptic processes.

Analyzing over six million records related to maternal and child health, the researchers discovered that the interference of these medications with cholesterol pathways was associated with a 1.5 times higher risk of autism in children.

And for each additional SBIM prescribed, the risk increased an additional 1.3 times. Women who took four or more SBIMs ended up more than twice as likely to have a child with autism.  

The study authors, from the University of Nebraska Medical Center, have urged pregnant women not to stop any of these medications abruptly without medical supervision. Instead, they encourage doctors to consider alternatives.

A new study has found taking common prescription drugs during pregnancy may increase the risk of a child being born with autism (stock image) 

‘Our findings do not suggest that these medications are unsafe for adults,’ Dr Karoly Mirnics, senior study author and dean and director of the UNMC Munroe–Meyer Institute, said. 

‘But they raise important questions about their use during pregnancy, a period when even small biochemical disruptions may have outsized effects on fetal brain development.

The findings come after a major Danish study found Tylenol use was not tied to a ‘significant’ risk of autism, despite claims from President Donald Trump and Department of Health and Human Services Secretary Robert F Kennedy Jr. 

The new study, published in the journal Molecular Psychiatry, looked at 6.14 million maternal–child health records from the Epic Cosmos database, which represent nearly one–third of all US births between 2014 and 2023. 

The team also evaluated prescriptions for 14 different SBIMs. They included the antipsychotics aripiprazole (Abilify) and haloperidol (Haldol), as well as the anxiety drug buspirone (BuSpar). 

Antidepressants included were bupropion (Wellbutrin), fluoxetine (Prozac), sertraline (Zoloft) and trazodone. 

The researchers also looked at beta blockers metoprolol, propranolol, nebivolol, as well as statins atorvastatin (Lipitor), pravastatin, rosuvastatin (Crestor) and simvastatin (Zocor). 

Collectively, these drugs account for about 400 million yearly prescriptions in the US. 

The above graph shows the comparison of autism incidence between children whose mothers used sterol biosynthesis–inhibiting medications (SBIMs) and those who did not

Of the 196,447 children diagnosed with autism, 14.2 percent had prenatal exposure to SBIMs. 

Additionally, use of SBIMs increased over time, from 4.3 percent of pregnancies in 2014 to 16.8 percent in 2023. 

The researchers found mothers who were prescribed at least one SBIM during pregnancy had a 1.5–fold increased chance of having an autistic child, and for each additional SBIM, the risk increased 1.3 times. 

Mothers who were taking four or more SBIMs during pregnancy showed a 2.3–fold increased risk of having an autistic child. 

The brain contains about 20 percent of the body’s total cholesterol, which creates synapses, or connections between neurons, along with protective membranes. Many children with autism, however, have low cholesterol, suggesting disruptions in their brains’ communication networks. 

The genetic disorder Smith-Lemli-Opitz syndrome (SLOS), affecting one in 20,000 US births, has also been shown to disrupt the brain’s cholesterol–producing pathway, and 75 percent of children with this disorder also meet the criteria for autism spectrum disorder. 

Stopping drugs such as antidepressants and beta blockers can lead to disastrous consequences, including withdrawal symptoms such as fever, chills, severe anxiety and heart palpitations. 

Instead, the researchers urge doctors treating pregnant patients to evaluate all medications that could have sterol–inhibiting effects and look for safer alternatives.