Low birth weight, prematurity may raise autism risk

By Anne Harding

NEW YORK (Reuters Health) - Low birth weight and preterm delivery increase the likelihood that a child will be autistic, with girls being at particular risk, researchers from the U.S. Centers for Disease Control and Prevention report.

"Pediatricians are probably sensitive to the fact that low birth weight children or children born too soon have special developmental needs," researcher Dr. Diana Schendel of the CDC's National Center on Birth Defects and Developmental Disabilities, told Reuters Health.

"This study simply supports that they should not overlook the behavioral aspects of development."

She noted that while boys far outnumber girls in the general population of children with autism, physicians "may need to be aware that they will see more equal numbers of boys and girls" with autism among low birth weight and preterm children, based on the current findings.

Schendel and colleague Tanya Karapurkar Bhasin based their results on a comparison of 565 autistic children with 578 children the same age without the disorder. All of the children were born in the Atlanta area between 1981 and 1993.

The researchers found that among low-birth-weight and preterm children, autism was less common than other developmental disabilities, such as cerebral palsy and hearing or vision loss.

However, children born weighing less than 2,500 grams -- or roughly 5.5 pounds -- had about twice the risk of autism as those with a normal birth weight. Similarly, children born before the 33rd week of pregnancy were twice as likely to develop the disorder as those born at full-term.

Girls seemed to be particularly at risk.