Premature babies benefit from being exposed to adult talk as early as possible, suggests research.
The study set out to test the association of the amount of talking that a baby was exposed to at what would have been 32 and 36 weeks gestation if a baby had been born full term, using the Bayley Scales of Infant and Toddler Development, 3rd Edition cognitive and language scores.
The research was led by Betty Vohr, professor of paediatrics at Women and Infants Hospital of Rhode Island.
It was hypothesised that pre-term infants exposed to higher word counts would have higher cognitive and language scores at seven and 18 months corrected age.
"Our earlier study identified that extremely premature infants vocalise (make sounds) eight weeks before their mother's due date and vocalise more when their mothers are present in the NICU (Neonatal Intensive Care Unit) than when they are cared for by NICU staff," explained Vohr.
The research was published in the online edition of the journal Pediatrics.
At 32 weeks and 36 weeks, staff recorded the environment for 16 hours with a Language Environment Analysis (LENA) microprocessor.
The adult word count, child vocalisations and 'conversation turns' (words of mother or vocalisations of infant within five seconds) between mother and infant are recorded and analysed by computer.
"Every increase by 100 adult words per hour during the 32 week LENA recording was associated with a two point increase in the language score at 18 months," noted Vohr.
"Our study demonstrates the powerful impact of parents visiting and talking to their infants in the NICU on their developmental outcomes," she added.
Historically, very premature infants are at increased risk of language delay.