No Link Between Maternal Health Conditions and Autism: New Study

An extensive study of over 1.1 million pregnancies shows that maternal health conditions are not a cause of autism. The findings highlight the role of genetics and environment, providing relief for many families.

A comprehensive new study led by researchers at NYU Langone Health concludes that maternal health conditions during pregnancy are not causally linked to autism in children. This research provides an important shift in understanding the factors contributing to autism, a developmental disorder characterized by challenges in social interactions and repetitive behaviors.

Published today in the journal Nature Medicine, the study analyzed the medical records of more than 1.1 million pregnancies documented in Denmark’s national registry. This extensive dataset allowed researchers to explore over 1,700 maternal health diagnoses and their possible associations with autism.

“Our study shows that there is no convincing evidence that any of these other diagnoses in the mother can cause autism,” senior author Magdalena Janecka, an associate professor in the Department of Child and Adolescent Psychiatry and the Department of Population Health at NYU Grossman School of Medicine, said in a news release.

The team found that nearly all supposed links between maternal sickness and autism could be attributed to other factors, such as genetics, environmental pollutants and health care access.

“We believe our study is the first to comprehensively examine the entire medical history of the mother and explore a wide range of possible associations, controlling for multiple concurrent conditions and confounding factors,” lead author Vahe Khachadourian, a research assistant professor in the Department of Child and Adolescent Psychiatry, said in the news release.

The unique structure of Denmark’s medical registry, which consolidates all health records under a single government-issued number, provided a robust framework for the study. This allowed the researchers to control for confounding factors like sociodemographic status and maternal age, which are known to influence autism diagnoses.

After adjusting for these factors and considering paternal health histories, the researchers determined that the only maternal diagnoses strongly associated with autism were complications related to the fetus. These findings suggest that such complications are early signs of autism rather than causes.

“Our interpretation is that these fetal diagnoses likely do not cause autism, but are instead early signs of it,” Janecka added. “Many mothers of children with autism feel guilty about it, thinking that they did something wrong during pregnancy, and it is heartbreaking. I think showing that these things are not going to cause autism is important and may lead to more effective ways to support autistic children and their families.”

Genetics play a substantial role in autism, and the team emphasized that certain genetic factors are more closely linked to the disorder. For instance, genes associated with depression in mothers may also contribute to autism in children, further complicating previous assumptions about maternal sickness causing autism.

In addition, the study analyzed fathers’ medical histories, revealing that many paternal diagnoses were just as likely to be linked to autism as maternal diagnoses. This finding strongly supports the influence of familial factors, both genetic and environmental, over maternal health conditions during pregnancy.

According to federal estimates, one in every 54 children in the United States is diagnosed with autism. This research provides a clearer understanding of the true causes of autism, emphasizing the importance of genetics and familial factors over maternal health conditions during pregnancy, and shifts the focus towards more supportive interventions for affected families.