Parents who are having difficulty getting their infant or toddler to stick to a consistent naptime and bedtime should consider reducing the amount of time their child watches television, study findings suggest.
"Regular sleep schedules are an important part of healthy sleep habits and help to prevent sleep problems such as night-time awakenings," Dr Darcy A Thompson, at the University of Washington in Seattle, said.
Parents who struggle with keeping their child on schedule should "think about how much media they're using", said Thompson's co-author, Dr Dimitri Christakis of Children's Hospital and Regional Medical Centre in Seattle.
Children in the US are known to watch more than 19 hours of television each week, but the American Academy of Pediatrics recommends that children under the age of two not watch any television and those older than two years watch less than two hours a day.
"There's a lot of reasons to minimise if not completely eliminate viewing in the first three years of life," said Christakis.
Studies conducted among children and adolescents reveal various adverse effects associated with television viewing, including obesity, aggressive behaviour, attention problems, poor sleep habits and disordered sleep.
Few researchers have investigated the effects of television viewing among infants and toddlers, however.
To investigate its influence on their sleep schedules, Thompson and Christakis analysed data from the National Survey of Early Childhood Health, on 2 068 children aged four to 35 months.
They found that children less than a year old generally watched less than an hour of television a day, but those aged 12 to 23 months watched 1,6 hours of television each day, and those 24 to 35 months watched more than two hours.
Also, about a third (34 percent) of children had irregular naptimes and more than a quarter (27 percent) had irregular bedtimes.
Overall, the more time children spent in front of the television, the more likely they were to have irregular sleeping schedules, they report in the medical journal Pediatrics.
The reason for the association between television viewing and sleep disturbances is unknown, but one theory is that the bright light of the television before sleep may interfere with the normal sleep/wake cycle, Thompson and Christakis note.
Also, rather than calming children before bed, TV viewing may stimulate them.
In light of the findings, Thompson recommends parents not only remove televisions from their child's room, but they also "closely monitor" their child's television viewing. - Reuters