Are There Ties Between Prenatal Ultrasound and Autism?

A controversial study recently published in JAMA Pediatrics has posed possible but largely unfounded links between autism and ultrasound technique and frequency. According to researchers from Boston University School of Medicine, there is a possible correlation between depth of ultrasound penetration during the first and second trimesters and autism.

The researchers evaluated sonograms of 420 children, 107 with autism, 104 with developmental delay, and 209 with typical development. They looked at the frequency of ultrasound scans and penetration depth amongst the three groups. They found that mothers of children with autism underwent shorter ultrasound procedures during the first and second trimesters than mothers with typically developing children. The researchers also determined that the autism group experienced a higher average of ultrasonographic penetration in comparison to both the developmentally delay and typical development groups. Specifically, 12.5 centimeters for the autism group vs 11.6 centimeters for the developmental delay and the typical development groups during the first trimester.

According to the study’s lead author, N. Paul Rosman, MD, a pediatrics professor at BU, these findings don’t indicate that ultrasounds provoke autism. "We think this study was done well, but there are deficiencies, and that's why we call for additional studies," he said.

In an article for CNN, a handful of physicians spoke out against the study’s conclusions. Thomas Frazier, PhD, the chief science officer at Autism Speaks told the news outlet that there isn’t “enough evidence to make a recommendation for or against ultrasound.” One physician with significant expertise in ultrasound use, Marvin Ziskin, MD, professor of radiology at the Lewis Katz School of Medicine at Temple University, said, “Unfortunately, the authors do not appear to know what is meant by the ultrasound penetration depth. It does not relate to the amount of ultrasound entering the body."

Half of autism cases are caused by disease or a genetic abnormality, and scientists don’t have a clear reasoning for the other 50 percent of cases. Despite the study’s subtle suggestions that the degree of ultrasound penetration might be associated with autism, Ziskin insists that the research “should give expectant mothers confidence that ultrasound will not cause autism spectrum disorder or delayed development.”