Autism Linked to Maternal Health Factors

Maternal health conditions during pregnancy were consistently associated with autism spectrum disorder but several factors varied across race and ethnic groups, a large retrospective study of U.S. children showed.

Autism prevalence differed by race and ethnicity, but most maternal health conditions during the perinatal period had similar relationships with autism, reported Magdalena Janecka, PhD, of NYU Grossman School of Medicine in New York City, and co-authors.

However, four conditions — maternal overweight and obesity, depression, asthma, and pregnancy complications — showed racial and ethnic differences in the magnitude of their association with autism, Janecka and colleagues wrote in JAMA Network Open.

All of these conditions had stronger associations with autism in white mothers than Black, Hispanic, or Asian and Pacific Islander mothers. This could reflect disparities in healthcare access, diagnostic practices, or unmeasured environmental and genetic factors, the researchers noted.

Overall, 2.4% of children were diagnosed with autism, with prevalences of 3.2 % for Black children, 2.9% for Asian and Pacific Islander children, 2.5% for Hispanic children, and 2.0% for white children.

“Most studies examining potential risk factors for autism assume that these effects are the same across different population groups, even though we know that there is a lot of room for variation,” Janecka told MedPage Today.

With maternal depression, for example, “women with limited access to healthcare, or women from ethnic minority groups, may find it harder to get a diagnosis and as a result have a more severe form of disorder upon diagnosis, or they may receive different medications once diagnosed,” she pointed out.

“Rather than averaging these effects across groups, we decided to start unpacking this variation,” Janecka said. “Our study explores race and ethnicity as one of the factors that could change what, for example, maternal depression means as a risk factor — but many other dimensions still need to be explored, like insurance status.”

Autism affects one in every 31 children by age 8 in the U.S., according to the most recent CDC data, with changing patterns among girls and children from racial and ethnic minority groups. While many factors may contribute to the rise in diagnoses, what causes autism remains elusive.

In 2025, President Trump warned pregnant women not to take acetaminophen (Tylenol) over an unproven link with autism, but numerous studies have demonstrated that prenatal exposure to acetaminophen is not associated with an increased risk in autism diagnoses.

Earlier research has documented links between several maternal conditions during pregnancy and autism in the offspring, including, obesity, diabetes, hypertensive disorders of pregnancy, asthma, and psychiatric conditions like depression and anxiety.

“With several maternal health conditions identified as associated with increased autism spectrum disorder in offspring, determining the reasons underlying these associations and identifying populations most impacted has garnered interest,” wrote Aisha Dickerson, PhD, MSPH, of Johns Hopkins Bloomberg School of Public Health in Baltimore, in an accompanying editorial.

In the current study, both maternal health conditions and autism diagnoses were assessed through health system records, she noted. “As advantageous as electronic health records have proven to be for large-scale observational studies, these metrics still require healthcare access,” Dickerson observed.

The findings support the hypothesis that mothers from more historically marginalized populations may continue to experience healthcare disparities and lower diagnostic ascertainment for adverse health conditions, she added.

“Overall, this study not only highlights a continued need for achieving equity in healthcare access but also suggests the mother-child race-identity paradigm deserves more consideration,” she wrote.

Janecka and colleagues followed 224,353 children in the Kaiser Permanente Northern California health system who were born from 2010 to 2017; of these, 5,448 were diagnosed with autism. The mean age at diagnosis was 3 years, and the mean maternal age at delivery was 31.9 years.

The study assessed 25 maternal diagnoses previously identified as being associated with autism. Mothers in the study cohort had a median number of two conditions; 53.4% had two or more conditions, and 10.7% had five or more conditions.

Of the 25 diagnoses analyzed, four had a statistically significant interaction term with maternal race and ethnicity, the researchers said. Two other factors — pain associated with female genital organs and menstrual cycle, and bipolar disorder — were not significant after multiple testing correction, they added.

Study limitations included a finite follow-up duration, which did not capture autism diagnoses made at later ages, Janecka and co-authors acknowledged. Other dimensions besides race and ethnicity also may contribute to the findings, they added.