Study details

For the study, researchers from the University of Nebraska Medical Center (UNMC) looked at 6.14 million maternal-child health records from the Epic Cosmos database, which represents almost a third of all U.S. births between 2014 and 2023. The database includes 300 million de-identified patient records from over 1,880 hospitals and 42,400 clinics.

Specifically, the researchers looked at births between January 2014 and December 2023, with a follow-up of at least 18 months after birth through available records up to January of this year.

The researchers looked at the association between SBIMs — which include certain antidepressants, antipsychotics, beta-blockers, and statins — and the risk of an ASD diagnosis in the child, specifically looking at 15 medications:

• Sertraline (Zoloft)
• Fluoxetine (Prozac)
• Bupropion (Wellbutrin)
• Buspirone (Buspar)
• Aripiprazole (Abilify)
• Cariprazine (Vraylar)
• Haloperidol (Haldol)
• Trazodone (Desyrel)
• Metoprolol (Lopressor)
• Propranolol (Inderal)
• Nebivolol (Bystolic)
• Atorvastatin (Lipitor)
• Simvastatin (Zocor)
• Rosuvastatin (Crestor)
• Pravastatin (Pravachol)

They found that mothers who were prescribed at least one SBIM during pregnancy had a 47% increased risk of having a child diagnosed with ASD. For each additional SBIM that was co-prescribed, there was a 33% additional increased risk of ASD, and mothers who were prescribed four or more SBIMs saw a 133% increased risk of an ASD diagnosis.

Of the 234,971 children diagnosed with ASD in the study, 15% had prenatal exposure to SBIMs.

The researchers also found that SBIM use during pregnancy increased significantly over time, rising from 4.6% of pregnancies in 2014 to 16.8% in 2023.

However, the authors cautioned the study is observational in nature and that its results don't suggest patients should stop taking SBIMs without medical supervision, as many of these drugs are essential and often life-saving treatments.

Rather, they said that more research is needed, along with a reevaluation of prescribing practices and the development of safer alternatives for use during pregnancy.

In addition, the researchers also called for the creation of a comprehensive list of all medications with sterol-inhibiting effects, an evaluation of all new drugs for any unintended sterol pathway inhibition, and an increase in provider education about medication-associated sterol disruption during pregnancy.

"Our findings do not suggest that these medications are unsafe for adults," said Karoly Mirnics, coauthor of the study and the dean and director of the UNMC Munroe-Meyer Institute. "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."