Washington (AFP) – One in 68 children has autism, a 30 percent rise over the last estimate released in 2012, U.S. health authorities said Thursday.

The latest U.S. data from the Centers for Disease Control and Prevention show that the “proportion of children with autism and higher IQ (is) on the rise,” said a CDC statement.

Previously, as many as one in 88 U.S. children were known to have autism spectrum disorder, or ASD, a developmental disorder that recent research suggests may originate in the womb.

“This new estimate is roughly 30 percent higher than previous estimates reported in 2012 of 1 in 88 children (11.3 per 1,000 eight year olds) being identified with an autism spectrum disorder,” said the CDC.

The findings were based on diagnoses of eight-year-olds at 11 U.S. sites in 2010.

The prevalence of autism varied widely, from one in 175 children in Alabama to one in 45 children in New Jersey.

The data continued to show that autism is five times more common in boys than in girls. In the United States, one in 42 boys is diagnosed with autism, compared to one in 189 girls.

The reasons for the rise were unclear, but the CDC said the criteria used to diagnose autism spectrum disorder and the methods used to collect data have not changed.

Ian BC North via Flickr