Autism diagnoses experienced a significant increase following the onset of the COVID-19 pandemic. However, this trend does not necessarily indicate a sudden rise in the prevalence of autism itself.
The surge in diagnoses was predominantly among girls and women, whereas the rates for boys and men either remained unchanged or decreased.
What might be the reason behind this trend?
A recent study published in JAMA Network Open proposes that many girls and women may have been overlooked in the past.
Researchers from Saint Louis University analyzed electronic health records from 171,134 individuals who consistently received care between 2016 and 2024 within a major US healthcare system.
Initially, the annual rate of newly recorded autism diagnoses decreased until 2020, after which it began to rise. Upon examining the data by gender, researchers discovered two distinct trends.

While diagnoses among males remained stable or declined, the rate for females increased by an average of 19 percent annually from 2020 to 2024.
The number of females receiving a new diagnosis nearly doubled, from 284 in 2016 to 513 in 2024.
The study indicates that the perceived post-pandemic rise was not uniform across the population. Instead, healthcare professionals may have improved in identifying autism in individuals whose characteristics were previously missed.
“Aggregate growth masked a significant sex disparity,” the researchers write.
Traditionally, autism has been diagnosed more frequently in boys and men. Screening tools and standard descriptions of autism were largely developed from studies involving males, potentially complicating the recognition of other manifestations.
A 2026 study published in The BMJ found that girls were diagnosed later than boys, but the difference in diagnosis rates significantly decreased by adulthood.
Autistic girls may exhibit higher social motivation or mask their challenges, making them harder to identify with conventional screening methods.
In the study, girls and women received autism diagnoses about three and a half years later than boys and men. Among children, girls were typically diagnosed about a year and a half later than boys.
The most notable increase was among teenage girls, with diagnoses rising by approximately 22 percent each year from 2020 to 2024. Researchers suggest many of these girls might have been missed during childhood and diagnosed only during their teenage years.
The timing does not conclusively establish that the pandemic directly caused the increase in autism or the broader diagnostic trend.
During the initial months of COVID-19, routine medical appointments, developmental screening, and in-person schooling were disrupted. Once these services resumed, previously postponed assessments may have resulted in a surge in diagnoses.
Telehealth, which gained wider acceptance for autism assessments, may have made evaluations more accessible. Additionally, growing public awareness, driven by women sharing their experiences online, could have encouraged individuals to recognize autistic traits in themselves and seek professional evaluation.

Notably, when researchers re-analyzed the data without the atypical 2020 figures, the overall pattern persisted: diagnoses increased for females while remaining stable or declining for males. In this analysis, the turning point for females shifted back to 2018.
This suggests that pandemic-related disruptions alone do not account for the trend.
The study has notable limitations. It tracked the first autism diagnosis recorded within one healthcare system, which might not represent each individual’s initial diagnosis.
Diagnoses were identified through billing codes and were not independently verified using standardized assessments or comprehensive medical-record reviews.
The predominantly White cohort was also limited to individuals consistently using the same healthcare system, so the findings may not be applicable to the broader US population.
Related: Scientists Identify 2 Distinct Subtypes of Autism in The Brain
Researchers thus examined changes in recorded diagnoses among people consistently engaged with the healthcare system, rather than changes in the underlying occurrence of autism.
Despite these limitations, the findings highlight a persistent diagnostic gap. Delayed recognition can postpone access to support, educational or workplace accommodations, and a community that aids in understanding their experiences.
The study implies that the rise in autism diagnoses may reflect healthcare systems’ increased ability to identify individuals who were previously overlooked.
The study was published in JAMA Network Open.
This article was fact-checked by Rachel Garner and edited by Peter Dockrill. While we pride ourselves on our process, we are only human. If you spot a mistake, please let us know.

