According to a study in Pediatrics, less than 50% of infants in the US always sleep on their backs — the position recommended by the American Academy of Pediatrics (AAP) to avoid sleep-related injuries and deaths.

More than three in four mothers said they usually placed their infants on their backs to sleep, the survey found. But just 44% of the mothers said they planned to place babies to sleep on their backs and then actually did this every time.

“Intention does not always match practice,” said lead study author Eve Colson of the Yale School of Medicine in New Haven, Conn.

In 1992, the American Academy of Pediatrics announced that babies should be placed on their backs to sleep, in order to lower their risk for Sudden Infant Death Syndrome (SIDS). Nationwide, SIDS kills about four babies out of every 10,000 live births, down from about 130 in 10,000 in 1990, according to the CDC.