Low weight at birth may increase a person’s chances of developing autism

THE QUESTION Might the tiniest of newborns face a bigger chance of developing autism?

THIS STUDY involved 623 children who were born in the mid-1980s weighing 4.4 pounds or less. Their health was assessed periodically, including screening for autism spectrum disorders at age 16 and evaluations to confirm the diagnosis, using standardized measures, at age 21. Overall, 5 percent of the youths had autism spectrum disorder diagnoses, a rate described as five times that found in the general U.S. population. The lower the birth weight, the higher the likelihood of an autism diagnosis, with a 10.6 percent prevalence among those who weighed 3.3 pounds at birth and a 3.7 percent prevalence at 4.4 pounds.

WHO MAY BE AFFECTED? Children who weigh less than 5.5 pounds at birth, considered a normal weight for 37 weeks of gestation. Children with autism generally have trouble communicating and interacting with others. Symptoms and severity vary, creating a range of developmental problems known as autism spectrum disorders. The cause is not known.

CAVEATS Some data during assessments came from questionnaires completed by the youths’ parents. No group of children who were born at a normal weight were included in the study, thus allowing comparison only to general population estimates.

FIND THIS STUDY November issue of Pediatrics (pediatrics.

LEARN MORE ABOUT autism at and www.
(click the parents’ site).

Linda Searing

The research described in Quick Study comes from credible, peer-reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.