Twenty-five percent of these toddlers tested positive on the M-CHAT, suggesting that they had an increased risk of developing autism. Factors that were significantly associated with a positive M-CHAT screen included lower birth weight, lower gestational age, being male, having an abnormal MRI, being ill when delivered, an infection in the mother before birth, or the mother experienced hemorrhaging during labor and delivery.
Limperopoulos said this study wasn't designed to determine causality, but that some type of prenatal or perinatal insult might increase the likelihood of autism.
"I think it's a great study," said Dr. Sara Hamel, a developmental pediatrician in the Child Development Unit at Children's Hospital of Pittsburgh. "A group of infants born preterm and at a low birth weight underwent screening for autism features, and about 25 percent screened positive. That doesn't mean they have it, but that they're at risk. This study really lends weight to the idea that if you screen children around 18 months old, you'll find a number of kids who test positive and need further diagnostic assessment."
The second study assessed some of the financial impact that having a child with autism can have on a family's finances, and found that when a child has autism, the family earns an average of $6,200 less each year, or about 14 percent.
"We think parents are making different decisions about labor participation," said study author Guillermo Montes, a senior researcher at Children's Institute in Rochester, in New York. "In some cases, one parent stays home, another may turn down a promotion or might take a job that doesn't require as much travel," which ultimately reduces the family's earning power.<
All rights reserved