The U.S. government is preparing a safety warning about baby slings -- popular infant carriers that parents can sling around their chests to carry their baby.

The concern is that infants can suffocate, and a few have.  Consumer Product Safety Commission Chairman Inez Tenenbaum says her agency is getting ready to issue a general warning to the public.

Safety advocates have cautioned that some slings, where the baby falls into a curved or "C-like" position inside the sling, can lead to suffocation by restricting the baby's breathing.