Retail giant Amazon is continuing to sell baby sleep positioners despite fears they can cause babies to suffocate.
Several other firms, including John Lewis and Tesco, have removed the products from their websites after US authorities issued a fresh warning to parents saying they were unsafe.
The US Food and Drug Administration (FDA) has linked the products to at least 12 baby deaths in America - which occurred when babies rolled from their side to their front and suffocated.
The positioners, which are sometimes called nests or wedges, are intended to keep the baby in one place on their back and are marketed as suitable for use up to six months of age.
Some parents use them hoping their baby will sleep longer due to the infant feeling cosy or "cocooned", while others believe they cut the symptoms of reflux.
While some retailers have taken action to remove the products from their websites, others, including Amazon and Jo Jo Maman Bebe, still have them for sale.
A spokeswoman for Jo Jo Maman Bebe said it was still selling the products but was "investigating the issue as a matter of urgency with our suppliers."
A spokeswoman for Amazon, which still has a range of sleep positioner products for sale, said the firm would not be commenting on the issue.
John Lewis has removed the Cocoonababy Sleep Positioner from sale. It still has a range of "nests" and "pods" for sale including the Cocoonababy nest and the Sleepyhead. A statement from John Lewis said: "We have one baby sleep positioner and as a precautionary measure we are removing it from sale."
A Tesco spokesperson said: "We have removed these products from our website as a precautionary measure."
A statement from the FDA said it was "reminding parents and caregivers not to put babies in sleep positioners.
"These products - sometimes also called "nests" or "anti-roll" products - can cause suffocation (a struggle to breathe) that can lead to death."
The FDA and the NHS recommend that infants sleep on their backs on a flat mattress in an empty crib.
The FDA said its safety advice was to "never use infant sleep positioners: "The federal government has received reports about babies who have died from suffocation associated with their sleep positioners. In most of these cases, the babies suffocated after rolling from their sides to their stomachs."