My daughter Gillian turned five in February and, so far, it's my favourite age. I love five because the developmental milestones at this age are truly exciting to me: reading short books, printing her name, attempting to ride a two-wheeler. However, there's just one big milestone that I'm still waiting for: sleeping through the night. I can count on one hand the number of times she's slept from dusk ’til dawn—which means I can use my other hand to hold my coffee mug, or, as I do most mornings, rub her back to soothe her during a tantrum. Those daytime tantrums are always worse after a night of frequent wakings.
Until recently, not much was known about toddler sleep and the long-term impact it has on emotions and behaviours. But new research out of the Norwegian Institute of Public Health, published in the journal JAMA Pediatrics, sheds light on how the lack of shut-eye during the toddler years can cause kids to be more emotionally reactive during the preschooler stage.
The study, which included 32,662 children, examined data collected over an almost 10-year period (1999-2008) from the Norwegian Mother and Child Cohort Study. Researchers looked at the mother-reported sleep habits of 18-month-olds and the later emotional well-being of those same children at the age of five.
At 18 months, almost 60 percent of toddlers slept up to 14 hours per night. Two percent of 18-month-olds slept less than 10 hours a night, and three percent woke up three or more times a night. The mothers of these kids who slept less than 10 hours a night and woke up frequently reported higher incidences of emotional and behavioural problems at age five, such as signs of anxiety and depression. Researchers discovered that the risks related to poor sleep habits was higher for internalizing problems than for externalizing problems (like aggression).
Even researchers who suspected a cause-and-effect link were still surprised at the results. "While only an experimental study can determine causality, our study does suggest that there is an increased risk of developing such problems, also after accounting for a range of other possible factors," lead author Borge Sivertsen told Reuters Health. The study suggests inadequate sleep leads to issues with handling emotions during the day—which could account for Gillian's outbursts.
Sivertsen also said that parents may be part of the reason why their toddlers aren't sleeping well. Developmental milestones, like the ability of a child to fall asleep on his own, are important. Well-intentioned acts, like rocking or singing your child to sleep, likely increases the risk for later sleep problems because kids become dependent on their parents to fall asleep.
Sleep studies like this always make me feel like I've messed up my kids, especially since I am a confessed co-sleeper and "rock-to-sleeper." Experts say these tactics disrupt kids' sleep, but, overall, my kids are happy and healthy. My best advice based on my own experiences: do what works for your family.
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