By Caroline Christ / Reuters Health
Parents who are waiting to begin the crib shift to bed up to three-year-olds may find that both they and their children are able to sleep better, the researchers say.
In a survey of parents and caregivers across five countries, those who delayed the transition from cradle to bed were more likely to report less resistance before bedtime, less wakefulness overnight and longer sleep duration for children, researchers write in the journal Sleep Sleep.
"Studies over the last decade have shown how important healthy sleep is throughout life, but especially during childhood," said study author Ariel Williamson of Children's Hospital in Philadelphia, Pennsylvania.
In previous studies, Williamson and his colleagues found that toddlers who avoided sleep tend to have more difficult time with chores, temper tantrums, and self-regulating behaviors.
"At this age, parents and caregivers are the ones who pay attention to them, and are affected by them, from the sleep of their toddlers," Williamson told Reuters Health on the phone. "It is important to record a therapist's report as an objective measure of sleep."
Williamson and colleagues collected data from 1,983 caregivers with toddlers aged 18 to 36 months living in Australia, Canada, New Zealand, the United Kingdom, and the United States. The data was submitted by therapists using Johnson's Babytime Baby Sleep application, a free smartphone application offered by Johnson & Johnson. J & J Consumer Inc also financed the research.
The study found that crib sleep rates declined steadily with age, with 63 percent of toddlers sleeping in the crib from 18 to 24 months, compared with 34 percent in the crib in 24 to 30 months and 13 percent from 30 to 36 months.
Sleeping in the crib was associated with lying to bed earlier, falling asleep earlier, waking up less at night, sleeping for more stretching during the night and less resistance before bedtime.
"What caught up with us was how incredibly consistent the benefits were in every toddler group," Williamson said. "That's what we see clinically, too."
In future studies, Williamson and the research team will use the app to investigate how parents begin to move to bed and what motivates them. In some cases, parents with another baby on the way begin to move their toddler to bed so they can use the crib again. Others begin the transition because their toddler climbs out of the crib or looks physically too large to stay in the current crib.
"Adults tend to see cribs like cages, but that's not how kids see them," said Lisa Meltzer, a child psychologist at the Jewish National Hospital in Denver, Colorado, who was not involved in the study.
"Children like small spaces, when they feel secure and comfortable with them," she said by e-mail. "If you see young children playing, they like to play under the table or in big boxes."
Other researchers are interested in developing a protocol that helps families make the bed-crib transition, as it can cause sleep problems that did not exist before.
"Some strategies already exist to help children stay in bed, like role-playing games, can also prepare children for this transition," said Sarah Honecker, a sleep psychologist at Riley Children's Hospital in Indianapolis, Indiana.
Sleep experts and pediatricians tend to recommend an adjustable crib that moves the ground to the ground as the child grows older, said Honaker. This helps the toddler get comfortable with a sleeping arrangement that feels more like a bed reduces injuries and falls if the child tries to climb out of the crib.
"A 3-year-old is expected to develop cognitive development to remember the rules of bed," she said in a telephone interview. "Buying a baby crib with an adjustable mattress can prevent parents from making a transition that their child will not be developmentally prepared for."