Many cases of so-called crib death, about one in eight, occur among infants who have been placed on sofas.
Dr. Jeffrey Colvin, a pediatrician at Children's Mercy Hospital in Kansas City, Mo., and colleagues analyzed data on 7,934 sudden infant deaths in 24 states, comparing those that occurred on sofas with those in cribs, bassinets or beds.
Previous research had shown that couches were particularly hazardous for infants. The new analysis, published in the journal Pediatrics, tried to identify factors significant in these deaths.
"It's not only one risk that's higher relative to other sleep environments," said Barbara Ostfeld, a professor of pediatrics at Rutgers Robert Wood Johnson Medical School who was not involved in the new study. "It's multiple risks."
Nearly three-quarters of the deaths occurred among infants age 3 months or younger, the researchers found.
Pediatricians have long advised putting infants to sleep only on their backs, alone and on a firm, flat surface without a pillow. The study found parents were more likely to lay their infants face down on a sofa than, for instance, face down in a crib.
There's a "fallacy that if I'm awake or watching, SIDS won't happen," Colvin said, referring to sudden infant death syndrome.
In the study, most parents shared the sofa with an infant. But sleep-deprived parents may be more likely than they think to fall asleep on the couch with their newborns. Some sofas slope toward the back cushions, making it easier for infants to get wedged where they cannot breathe.
