Researchers Tie Low Birth Weight to Autism

PHILADELPHIA -- Autism is far more common in low-birth-weight babies than the general population, researchers are reporting Monday, a significant finding that nevertheless raises more questions than it answers and illustrates how little is known about a group of disorders that affect nearly 1 percent of American children.
The study found that 5 percent of newborns weighing less than 4 pounds, 7 ounces were later diagnosed with an autism spectrum disorder, as were nearly 11 percent of a subgroup born below 3 pounds, 5 ounces.

Study: Autism Risk Factors Elusive

Research has hinted that various factors around the time of birth may raise a child's risk of autism later in life, but there is still too little evidence to point to specific culprits, a U.S. study said.
Experts have long believed that genes play a key role in autism risk, but a U.S. study released last week found that genes appeared to explain a much smaller portion of the risk than previously suggested.
The latest study, a review published in Pediatrics of 40 previous studies, found that factors including low birth weight, fetal distress during labor and signs of "poor condition" in the newborn, such as problems with breathing or heart rate, have been linked to the risk of autism.