Normal Infant Sleep Part 5
Wouldn’t it be nice if infants and children wanted to sleep exactly where we wanted to put them on a given day? No joke here – it would be wonderful, but unfortunately it’s not how most babies sleep. We’ve heard of moms complaining about having to be outside walking for a nap to happen while living in cities with blizzards and 30 below weather, or needing to be walking constantly (inside or out) meaning naps are not only not a time of respite for mom, but can be downright unpleasant.
Interestingly, the most common situations involve touch, sound, or movement, three things that are abundant for the infant while in the womb. Recall that human babies are born at least 9 months early compared to other animals because of head size (if they got any bigger they could not get through the birth canal; see Trevathan, 2011), so for at least 9 months their bodies expect an “external womb.” So is it much surprise that outside the womb they expect the same things to lull them to sleep? With respect to touch, we know that oxytocin plays a huge role in feelings of contentment, security, and love, all of which affect the quality of our sleep (Uvnäs-Moberg, 2003). So it is not difficult to imagine that infants who are physically close to their caregivers, experiencing a release of oxytocin, are much more likely to fall asleep and remain asleep.
A second factor is sound – most notably the caregiver’s heartbeat, a sound that is highly familiar to infants from their time in the womb. When it is the mother holding the infant, her heartbeat, voice, and breathing can all offer a form of white noise which helps an infant feel safe and remain asleep, though the same effects can happen when another caregiver holds the infant as well. When this is not possible, the use of a white noise machine to block out some of the more abrasive sounds of our environment while still providing background noise can help with infant sleep. These white noise machines have been successful in inducing infant sleep (Spencer, Moran, Lee, & Talbert, 1990), and at assisting some parents achieve better sleep (Lee & Gay, 2011).
The third factor, movement, was also abundant in the womb, with baby in a soft, liquid pouch being swayed regularly. Remember how your baby was always awake in utero when you were resting? It’s because he or she was sleeping while you moved. Modern parents in Western cultures often focus on the car ride to get their infants to sleep. The lull of the car coupled with the snugness of the car seat can send many infants into a drowsy state, allowing them to nap contently while parents drive aimlessly around. However, the same movement-induced sleep can be gained from the use of a stroller, providing mom or dad with the ability to run errands or go for a walk or run. Possibly best of all, babywearing promotes movement, touch, and sound, all while allowing the caregiver to run errands and generally go about one’s life. Babywearing may provide the best form of an “external womb” for developing the baby’s brain and body in optimal ways (Narvaez et al., 2013).
The take-home point, though, is that it is normal for infants to prefer to sleep in contact with others rather than away from what many people would consider the “ideal” sleep space. Even though adults may prefer it, a bed in a quiet room is not necessarily ideal for infant naps. For a summary of napping behaviour and safe napping behaviour when wearing a baby, please click here for a great handout from ISIS (Infant Sleep Information Source).
A Final Summary
Over these three posts, we hope we have made it clear that often what parents perceive to be problematic infant sleep patterns that require “fixing” are actually quite normal and developmentally appropriate. We are cognizant of the fact that many families still find infant and toddler sleep to be a problem, which is why we are also focusing on writing about how to gently help with infant and toddler sleep. What we hope parents take home from this series is (a) a better understanding of the broad array of behaviours that constitute “normal” when it comes to our children’s sleep, and (b) that if the behaviour is not posing a problem for the family, you can rest assured the child is not suffering from these very normal sleep behaviours. Instead of following a particular expert’s advice, understand what is needed to keep babies safe when they sleep and build the sleep environment around these safe behaviors… then do what works best for your child. Let your child be your guide.
Posts in Sleep Series:
Also, check out: Dangers of "Crying it Out"
Series Varying Co-Authors
Tracy Cassels, University of British Columbia, www.evolutionaryparenting.com
Sarah Ockwell-Smith, babycalming.com
Wendy Middlemiss, University of North Texas
John Hoffman, uncommonjohn.wordpress.com
Kathleen Kendall-Tackett, Texas Tech University, http://www.uppitysciencechick.com/sleep.html
Helen Stevens, Safe Sleep Space
James McKenna, Mother-Baby Behavioral Sleep Laboratory, University of Notre Dame, www.cosleeping.nd.edu
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