Many busy moms and dads swear by the slings, which let a parent "wear" their baby while going about daily life. But the Consumer Product Safety Commission has received reports of 14 children who have died over the past two decades. Twelve of them were less than four months old.
"Parents of children younger than four months of age are really urged to take a lot of caution on whether they put their baby in these slings," the commission's Scott Wolfson told ABC News.
A consumer alert released by the agency today says newborns are at particular risk because they have weak neck muscles which make it difficult for them to move to a better position if they are suffocating.
"The sling's fabric can press against an infant's nose and mouth, blocking the baby's breathing and rapidly suffocating a baby within a minute or two," the warning reads. "Additionally, where a sling keeps the infant in a curled position bending the chin toward the chest, the airways can be restricted, limiting the oxygen supply. The baby will not be able to cry for help and can slowly suffocate."
Don Mays of Consumer Reports asked the CPSC to look into the issue a few months ago.
"I think the alert was very appropriate...it gave information to consumers about the hazards associated with sling carriers particularly the risks associated with very young infants who can suffocate."
One infant who died last year in an Infantino SlingRider model was only six days old. Lisa Cochran and Jerrid Fowler of Oregon were out with their newborn son Derrick in a sling while shopping.
"I was told it was the greatest way to bond, especially being a breastfeeding mother," Lisa Cochran told ABC News. " And now I wish I would have never bought it ... I would have never picked it off the shelf."
Their attorney, Brian Whitehead, says the coroner's report listed Derrick's cause of death as "positional asphyxiation." The family is suing Infantino.
"Our allegation in the lawsuit is that this particular sling and its design is such that, when a baby is in the sling, it causes the baby to curl in on itself, causing the baby not to be able to breath," Whitehead told ABC News.
Consumer Reports in fact, thinks the Infantino SlingRider is so dangerous, it has asked the CPSC to recall it.
The CPSC did not issue any recalls today, but said in its warning statement that it is continuing to investigate "to determine what additional action may be appropriate."
Infantino, released a statement today in response to the warning: "While Infantino believes that its SlingRider baby sling is a safe product, the company is working with the CPSC to address the agency's concerns and those of any parents and caregivers," it said. "As always, we will provide our customers with updates when we have more information."
The nonprofit group Babywearing International issued a statement to ABC News today urging parents not to give up altogether on the idea of slings.
The statement read, in part, that "wearing an infant in a well-constructed carrier and using proper babywearing techniques are of utmost importance. When done properly, babywearing is a safe and beneficial parenting tool."
Mays says while he was pleased with the CPSC warning, he was concerned that it did not address another issue: reports of babies slipping out of the slings.
"We recorded 37 injuries associated with children falling out of slings and those injuries associated with that include things like skull fractures, broken arms, serious lacerations, serious bruising," Mays said.
The CPSC, Mays said has been working behind the scenes to get sling makers to develop tough industry-wide safety standards until the government can come up with mandatory rules. In particular, ASTM International, an organization that works with industry and regulators to develop voluntary standards for everything from concrete to cribs, is finalizing sling safety standards.
"The ASTM standard making process is slow and painful," Mays said. "As a member of those committees I can tell you that first hand. However, if you try to go through the rulemaking route at CPSC it takes even longer."
The CPSC offered advice for parents, saying they should "make sure the infant's face is not covered and is visible at all times to the sling's wearer. If nursing the baby in a sling, change the baby's position after feeding so the baby's head is facing up and is clear of the sling and the mother's body. Parents and caregivers should be vigilant about frequently checking their baby in a sling."
The agency also said parents of babies with low birth weight or breathing problems should be extra careful as those two factors were present in some of the deaths involving slings.