The head of the Consumer Product Safety Commission, Inez Tenenbaum, said Tuesday that her agency is getting ready to issue a general warning to the public, likely to go out this week, about the slings.
"We know of too many deaths in these slings and we now know the hazard scenarios for very small babies," said Tenenbaum. "So, the time has come to alert parents and caregivers."
Tenenbaum spoke at a meeting of the Juvenile Products Manufacturers Association, an industry trade group that certifies certain children's products, including soft infant carriers.
Tenenbaum did not single out any specific baby slings or discuss the number of deaths linked to them. But there have been complaints for a couple years now about some baby carriers.
In 2008, Consumer Reports raised concerns about the soft fabric slings and some two dozen serious injuries, mostly when a child fell out of them. A follow-up blog warned about a suffocation risk and linked the slings to at least seven infant deaths.
Consumer Reports, published by Consumers Union, complained about the "SlingRider" by Infantino. The "bag style" sling wraps around the parent's neck and cradles the child in a curved or "C-like" position, nestling the baby below mom's chest or near her belly.
It's the "C-like" position that causes safety advocates to shudder. They say the curved position can cause the baby, which has little head and neck control in the early months, to flop its head forward, chin-to-chest -- restricting the baby's ability to breathe.
Another concern: that the baby can turn its face toward mom's chest or belly and smother in the parent's clothing.
Infantino's "SlingRider" was recalled in 2007 for problems with the plastic sliders on the sling's strap. But there have been no recalls because of a suffocation risk.
A message seeking comment was left with an Infantino representative.
About a dozen other sling or front-wearing baby carriers have been recalled since 1997, but they all also involved concerns about the babies falling from the slings because of problems with the fasteners, stitching and shoulder straps.
Tiffany Speck, of Kansas City, Mo., also has been warning about slings where the baby falls into a chin-to-chest position.
"You wouldn't want to put a baby in there," said Speck, a nurse who teaches classes on wearing slings properly. "The baby is curling, head toward toe, and what happens is the baby occludes its own airway."
Speck owns a company called BabySoSmart.com and sells her own baby slings. She recommends that babies in slings remain in an upright position, with the baby's tummy facing the mother's.