Health officials now estimate that 1 in 110 children have autism.
The Centers for Disease Control and Prevention released the new estimate Friday. It's a small change from a 1 in 100 estimate that CDC officials made in October. CDC officials said that estimate was preliminary and the new number comes from a completed analysis of reports from 11 states.
Previously, the CDC had been saying autism occurred in 1 in 150 children. The new estimate looks at 8-year-old children who had been diagnosed with an autism spectrum disorder in 2006.
The increase may be due in part to changes in how often autism is diagnosed. The CDC is studying possible environmental causes as well.