Premature babies tend to be slower to learn language skills than full-term babies. A new study reported in the journal Pediatrics found that the delay may be due to a lack of exposure to language in the hospital.

The new study sought to explore the sounds heard and uttered in neonatal intensive care units. Each of the 36 preemies in the study was fitted with a vest containing a digital recording device that captured sounds in the environment, including the infants’ own vocalizations over two 16-hour periods.

Surprisingly little language was found to be spoken in the babies’ environment. The majority of the sounds recorded included monitor sounds, general hospital background noise, or silence.

However, the children in the study – born, on average, during the 27th week of pregnancy -- vocalized more, making short vowel sounds, when they heard adults talk, especially their own parents. The babies’ vocalizations came within seconds of the parent speaking.

Says lead researcher Dr. Melinda Caskey, a pediatrician at Women and Infants Hospital in Providence, R.I.: "We'd want both parents and nurses to talk to the infants more in their daily interactions."