The most common cause of injury deaths in babies younger than 1 year is unintentional suffocation, and almost all of these deaths are preventable, a new report found.

Researchers used a federal government case registry to look at the causes of infant deaths by injury between 2011 and 2014. Of 1,812 sudden and unexpected infant deaths during that period, about 14% were caused by accidental suffocation.

Of these, 69% were caused by soft bedding; 19% were overlay deaths, in which a caregiver rolled over on the baby; and 12% happened when the infant was trapped between two objects, usually the mattress and a wall. The analysis appears in Pediatrics.

About 71% of the overlay deaths occurred in an adult’s bed, as did 49% of the soft bedding deaths, where blankets, pillows or soft toys covering the airway were the most common cause.

The American Academy of Pediatrics recommends that babies be put to sleep on their backs, that the crib have no soft bedding or soft objects, and that adults never sleep in the same bed with a baby.

“This paper supports the AAP recommendations,” said lead author Alexa Erck Lambert, an epidemiologist with the Centers for Disease Control and Prevention. “And it shows that these deaths by suffocation could have been avoided if the babies had been placed properly.”