The Food and Drug Administration issued a firm statement against the use of infant sleep positioners, such as the “wedges” or “nests” many new parents turn to with the hope of getting more shut-eye.

In a new safety alert released this week, the FDA said the use of an infant sleep positioner “poses serious suffocation risk and is unnecessary.” The updated guidelines cited reports where babies died after rolling onto their stomachs from use of the positioners—with more newborns “found in other, dangerous positions within or next to these products.”

For parents, the appeal of infant sleep positioners is understandable: Whether used with the hopes of soothing reflux or for co-sleeping, many of the products claim to be safe alternatives to flat cribs.

But the FDA says there are no comprehensive studies to support those safety claims: “Be aware that any product that claims to prevent or reduce the chance of SIDS has never been cleared or approved for that use by the FDA. The FDA discourages consumers from purchasing any product claiming to reduce a baby’s SIDS risk. These products are not proven to prevent SIDS.”

According to the National Institute of Child Health and Human Development, babies should sleep on their own, on their backs and in a crib free from blankets, pillows or products like sleep positioners.

Or it may help to remember the ABCs of safe infant sleep practices as recommended in the FDA‘s new video:

  • A for Alone
  • B for on the Back
  • C for in a Crib

That’s because even with the helpful claims of some infant sleep positioners, the best bet for a good night’s sleep is when you have the peace of mind that baby is safe.