US autism diagnoses surge, especially among girls, after COVID pandemic

Autism prevalence in the United States has risen dramatically over the past five decades, from an estimated two to four cases per 10,000 children in the 1960s to about 1 in 31 today. The increase has sparked debate over whether autism is becoming more common or whether improved awareness and broader diagnostic criteria are responsible.

A new study of electronic health records from a large US health system found that the post‑COVID‑19 rise in autism diagnoses was driven almost entirely by girls and women. From 2020 to 2024, new diagnoses among teenage girls grew about 22 % per year, while rates for boys remained stable or declined. Researchers concluded that the surge reflects better detection of autism in females, whose symptoms have historically been under‑recognized by screening tools developed primarily on male populations.

Experts such as Joseph Buxbaum of Mount Sinai and Amy Lutz of the University of Pennsylvania note that surveillance data, like the CDC’s Autism and Developmental Disabilities Monitoring Network, highlight the trend but do not explain its cause. The findings suggest that changes in diagnostic practices, rather than a sudden increase in the disorder itself, are driving recent numbers.