Rock-a-Bye Baby, Gently, You Swing

Now sound asleep until the morning light

Each night, as you tenderly sing this lullaby to your precious one, you witness their peaceful descent into slumber. Tucking them in comfortably, you dim the lights and return to your own restful bed. This simple act, sleep, integrates seamlessly into our daily routine yet is a cornerstone of our overall well-being. It not only offers essential rest, but also rejuvenates our body, rekindling it to optimal functionality. This has inspired widespread academic interest in “sleep health” and the intricate link it shares with holistic human health.

An array of studies have highlighted the significance of sleep for children’s health, optimal well-being, and overall development. It’s shown that children with adequate sleep, in terms of both duration and quality, generally have better psychosocial health. This reduces their risk of both mental and physical health complications. In essence, research evidence reinforces that well-rested children typically exhibit a better quality of life. Robust evidence supports the assertion that children, when provided with sufficient sleep, have a lower propensity towards conditions associated with adiposity such as being overweight or obese. Additionally, sound sleep promotes better emotional regulation in children, subsequently minimizing their vulnerability towards psychosocial health challenges including depression and anxiety. Given these numerous benefits, it becomes evident that well-rested children demonstrate improved academic performance and cognitive functioning. Up to this point, we might all have a better understanding of why nothing beats a good night’s sleep.

But have you ever paused to ponder these two salient questions: What exactly is “sleep”? And how does “sleep” impact me?

Human sleep predominantly comprises two states: Rapid Eye Movement (REM) and Non-Rapid Eye Movement (NREM) sleep. The latter can be further categorized into three stages – stage 1 (N1), stage 2 (N2), and stage 3 (a combination of N3 & N4). Conventionally, when we “fall asleep”, we progress from the stages N1, N2, N3+N4 to REM sleep, and then return to N1, completing one cycle. As adults, we usually complete approximately 4 to 6 such cycles in our sleep, with each cycle lasting roughly 90-110 minutes. In the context of a full night’s sleep, we spend around 75%-80% of our time in NREM sleep and the remaining 20 to 25% in REM sleep.

Each stage of sleep features unique patterns and levels of arousal:

This is the initial stage where we gradually transition into “sleep mode” from our wakeful state. Spanning just a few minutes, this stage is often characterized as the lightest phase of sleep. During N1, our muscles begin to relax and our heartbeat and breathing slow down.

The duration of this state within a single sleep cycle typically ranges from 1 to 7 minutes, accounting for approximately 2% to 5% of a night’s sleep.

In stage N2, our body begins to experience a drop in temperature accompanied by slowed breathing and heart rate. Brain activity also commences to decelerate after a few short bursts that pre-empt us from waking up in response to stimuli in our surroundings.

This stage generally lasts from 10 to 25 minutes in each sleep cycle and comprises around 45% to 55% of a night’s sleep.

During stages N3 and N4, we enter deep sleep. Our muscles, breathing, and heart rate further relax during this phase. An abundance of research evidence suggests this stage is paramount for our overall well-being, contributing to restoration, recovery, and bolstering the development of our mind and reinforcing our immune system.

This stage typically lasts from 20 to 40 minutes in each cycle, with N3 constituting about 3% to 8% and N4 constituting around 10% to 15% of a night’s sleep.

The REM state is when we dream. This stage is characterized by increased breathing and heart rate, along with heightened brain activity. 

The duration of the REM sleep can vary widely, generally between 10 to 60 minutes in each sleep cycle, making up approximately 20% to 25% of a full night’s sleep.

Children’s Sleep Schedule

Children’s sleep patterns distinguish significantly from adult schedules. Generally, children have an abundance of deep NREM sleep during the first few hours after falling asleep. As the night progresses, their sleep phases shift more towards REM sleep and lighter NREM sleep, resulting in more frequent awakenings during this latter half of the night compared to the beginning.

Regarding sleep cycles, the duration tends to increase as children age. For example, three-year-old children typically exhibit sleep cycles around 60 minutes. As they reach the age of five, their sleep cycles begin to approximate adult lengths, around 90 minutes per cycle. Understandably, children’s sleep duration fluctuates as they progress through various developmental stages.

Please note that this table primarily serves as a guide. As every child is unique, individual variations in sleep patterns can be expected.

Sleeps in Children among Stages:

During this phase, newborns are in the process of forming sleep cycles. They not only have to adapt to life outside the womb but also learn to regulate physiological needs like maintaining breathing and body temperature and coping with environmental factors like light and sound. Research indicates that newborns sleep between 10-18 hours per day, often longer for premature babies. Although 18 hours may seem extensive, it is typically divided into several sleep sessions throughout the day. New parents often find this newborn ‘polyphasic’ sleeping pattern challenging as it disrupts the typical adult routine.

By approximately three months, most infants start displaying a more structured sleep pattern, typically sleeping for longer periods during the night and remaining active during the daytime. Infants usually devote 10-12 hours to nighttime sleep and 3-4 hours to daytime naps. Most six-month-old infants begin reducing napping frequency to twice a day, coupled with progressive increases in nighttime sleep duration. Despite frequent 1-3 times night awakenings, only few (16.5% at three and 22.3% at eight months) reportedly sleep through the night without any negative impact on their developmental trajectory.

Usually, by 18 months, most toddlers transition from two daytime naps to one, coupled with 10-12 hours of nighttime sleep. This shift is accompanied by a decrease in night awakenings, while total sleep time ranges from 10-14 hours. During the second year, there is a significant decrease in the number of nighttime arousals.

As toddlers grow older, sleep duration gradually decreases with diminishing daytime napping. Total sleep time generally reduces to 11 to 12 hours per night, adhering to a monophasic pattern. Some children start experiencing sleep initiation problems around the age of three, amplified by a hectic daytime schedule and rapid cognitive and imaginative development. Instances of bedtime resistance and fears related to the dark or nighttime may emerge at this stage, but most children outgrow these issues as they age.

Most children within this age bracket establish solid nighttime sleep routines, typically sleeping for around 10-11 hours while maintaining alertness throughout the day. School performance often serves as an indicator of their sleep quality. Research revealed that insufficient sleep is associated with reduced cognitive function, particularly in the areas of attention and memory, which can significantly deter academic performance.

As children transition into adolescence, hormonal changes and shifting schedules influence their sleep patterns. While adolescents ideally need around 9 hours of sleep, physiological and practical factors often limit them to about 7 hours. Some might require an early afternoon nap to refresh for optimum functioning. Busy schedules between schoolwork, sports, or work often intensify the problem of sleep deprivation. Cumulative sleep debt, brought on by multiple factors, can negatively affect daytime functioning. Hence, it is vital for adolescents to maintain good sleep hygiene and consistent routines to optimise their ability to navigate their demanding schedules.

Can I Assist My Child’s Sleep?

Indeed, there are multiple ways to support your child’s sleep patterns:

1. Foster a Comfortable Environment:

  • Ventilate the room properly to ensure fresh air circulates.
  • Maintain a comfortable room temperature. Research indicates that maintaining a slightly cool room, around 16-22°Celsius, supports sleep by facilitating the secretion of melatonin. This, in turn, contributes to a more restful night’s sleep.
  • Use hypoallergenic blankets and bed sheets. Organic cotton or wool can be a good choice.
  • Manage lighting appropriately. Ensure the room is well-lit during the day and dim at night. Some children may find a completely dark room disconcerting. A night-light can be reassuring, as it allows the child to recognise familiar surroundings.
  • Consider swaddling newborn and infants gently in a light, breathable blanket. This can make your little one feel more calm and secure.

2. Establish Bedtime Routine Early:

  • Guiding children towards bed when they begin to display signs of sleepiness, while still alert, is highly beneficial. This practice encourages children to go to bed independently and fosters their ability to self-soothe and transition into sleep autonomously. 
  • Establishing consistent bedtimes and wake-up times for children, applicable to both weekdays and weekends, is a good idea. Adhering to this schedule helps instil a routine, reinforcing their internal body clocks and promoting healthier sleep patterns.
  • Create a sleep-promoting routine, such as taking a warm bath an hour before sleep, brushing teeth, drinking warm milk, or reading a bedtime story.
  • As children grow older, remove electronic devices from the bedroom to promote peace of mind.
  • Avoid large meals and caffeine intake close to bedtime.

3. Distinguish Day and Night:

  • Engage actively with your child during the day and encourage them to participate in different activities. Being responsive to your child’s needs and giving them attention during the day fosters their alertness and maintains interest in daytime activities. This approach is conducive to building a robust daytime-night-time routine, effectively differentiating between periods of activity and rest.
  • Read your preschool and school age child’s signs of sleepiness, such as yawning or droopy eyelids. Allow them to rest but limit nap time to no more than 4 hours during the day.
  • As bedtime approaches, engage your child in quiet activities to help them wind down.

4. Be a Role Model!

  • As a parent or caregiver, demonstrate good night-time routines and proper sleep hygiene practices. Children will observe and gradually emulate these habits.

Here are the main information and tips around ways to support healthy sleep habits in children. If you face challenges in establishing night-time routines for your child, consider seeking professional advice from your paediatrician or a public health nurse.
Stay tuned for more sleep-related information. Thank you for reading, and here’s wishing you and your little one refreshing sleep!

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