Setting the Scene for Sleep
Sleep is Individual and Changeable
As well as looking at guidelines to determine your baby’s sleep requirements, look for clues that come from your observations of her behaviour. You know your child best, and you will often be able to tell her sleepy signs and what she needs when she’s tired.
Apparently, humans spend on average one third of their lives sleeping. Newborns can spend up to 18 hours sleeping, and even by age two a child may spend more time asleep (in total) than awake. All in all, it’s said that almost 40% of childhood is spent snoozing.
It's a basic need, and it is important for children and adults alike. We all know this, and you may have a child who sleeps well, or you may have a child whose sleep pattern seems to change on a regular basis, or even to get just the bare minimum. With all the research, media and parent attention on sleep, it can feel confusing or tiring to figure out whether your little one is sleeping well and getting sufficient sleep. A rule of thumb seems to be: if he seems rested, happy and energetic when awake, he probably is getting enough kip. Recent research has actually found a genetic connection when it comes to sleep requirements. In other words, sleep needs and sleep patterns may ‘run in the family’. So look at your own sleeping pattern and those of others in the family, and see if there are any clues to how your child sleeps.
Still, your child is going through changes on a regular basis. Her growth and development is exciting, also for her, as she is constantly learning new skills and seeing the world differently each step of the way. But your child also has to cope with physical pains such as teething, and emotional pain such as separation anxiety. Additionally, adjusting to a 24 hour day/night pattern and learning to settle and sleep through the night are no small feats. You can find more information about sleep at different stages in DREAM, and Sleep Angels have key tips on how to help your child sleep like a baby.
This article outlines what research says about the basic importance of sleep, how your child sleeps (different to how you sleep), and developing the daytime/night time pattern (circadian rhythm). It can be useful to understand a little bit about how sleep happens; it may help you when you are observing your little one’s growing sleep patterns and finding the best ways to help support and promote positive, healthy sleeping habits.
The Importance of Sleep
As a parent you may be as preoccupied with your child's sleep as most parents seem to be. At least, you probably find it’s a common topic of interest (sometimes a topic of desperation). This is because sleep is precious. The nights you manage to get a 'normal' amount of sleep feel like the best treat you’ve had in a long time. Both daytime napping and night-time sleep are precious for children's learning, energy and wellbeing, but also for parents' wellbeing and their sanity. Both parties need sleep to recharge their batteries and enter the new day with the positive outlook and energy it deserves.
At the heart of the issue is the fact that you know that sleep plays an important role during childhood. The following areas are found to be affected by good quality and sufficient sleep:
- Development. Sleep is critical for the brain and body to develop, which explains why babies spend so much time asleep. Night-time sleep is when your child’s body produces more of the Growth Hormone (GH), which stimulates growth, cell reproduction and regeneration.
- Learning. Your child is consolidating her learning during sleep. She learns constantly, as new discoveries are made and new skills are mastered. Each time she enters a new development stage, you may notice that she is more tired and perhaps sleeps longer than usual.
- Dream sleep (REM) is an important part of your child’s sleep, as this is when his developing brain processes events and learning that has occurred (brain plasticity, or connections between nerve cells). This allows him to consolidate new learning and therefore change his behaviour (new skills). Dream sleep is also important for laying down long-term memories.
- Performance. Research shows that your child is likely to better be able to control her impulses, remember things, and adapt her behaviour when getting a good night’s sleep.
- Skills development. Studies have found that both having a regular routine and an earlier bedtime (before 9pm) ensures children falling asleep more easily and a longer sleep. This, in turn, impacts positively on emerging language, reading and math skills.
- Health. Sleep is an important determinant of future body composition in young children. Studies have found that young children who do not get enough sleep are at increased risk of becoming overweight later.
The Perfect Amount of Sleep?
You already know the answer: The perfect amount of sleep will be individual. But it can still be very useful to remind yourself from time to time: that sleep patterns are different for different children. How much sleep your child gets at night, how long daytime naps are, when she stops wanting daytime naps, and how easily she finds it going to sleep. Rather than comparing what happens in other families with your experience, focus on what your child’s sleep pattern is like and what you can do to best support and encourage restful and sufficient sleep. As a rule of thumb, if your child seems rested, happy and energetic after sleep, she is probably getting enough kip. If she often is irritable, agitated and lacking energy, she may need more rest.
You know your child and his needs best, and you learn to read the signs of when he is tired, when he has had enough or too little sleep, and what he needs to soothe himself into dreamland.
However, seeing as sleep plays such an important role during childhood, below is a research-based guideline. Please note that it is just that – a guideline. The purpose is to help you get an idea of whether your child is getting about the right amount of sleep she needs for her age. (Note the hours are listed as average number of hours in total, i.e. including daytime naps).
If you feel that sometimes your child is showing all the signs of being ready for sleep, but somehow sleep doesn’t happen or is a bit of a struggle, you may find some useful hints and tips in Sleep Angels.
0-3 months: On average between 14-18 hours in total
3-6 months: On average 14-15 hours in total (more regular pattern starting towards 6 months)
6-12 months: On average 14 hours in total (may have 2-3 naps during the day)
1-2 years: On average 14 hours in total
2-3 years: On average 12-13 hours in total
3-4 years: On average 12-13 hours in total (some still nap at this age, others have stopped earlier)
4-5 years: On average 11-12 hours in total (all sleep may now occur during the night)
Patterns of Sleep
This section contains information around the ‘science of sleep’. You can read about the patterns and stages of sleep, what they tend to look like for your newborn, and how they change as your child grows.
1. What is Sleep Made of?
To understand your child’s sleep, you can think of sleep as being divided into two stages – active sleep and quiet sleep. A sleep cycle is the total time spent going through both active and quiet sleep.
Active sleep is when we dream, and this stage is characterized by rapid eye movements (REM), and is often referred to as REM sleep or dream sleep.
Quiet sleep (or non-REM sleep; NREM) consists of four phases: drowsiness, light sleep, deep sleep and very deep sleep.
2. Sleeping Like a Baby
Your baby’s sleep looks very different to yours; it involves shorter cycles and more active sleep. When your newborn falls asleep he first enters an initial period of REM or dream sleep (lasting up to 20 minutes), and then progresses through quiet sleep, before he enters dream sleep once more and starts the whole cycle all over again. Each sleep cycle (there are several during the night) is likely to last 50 minutes at the most.
As an adult, you move quicker towards deep sleep, without entering a period of active sleep first. Your sleep cycles last about 90 minutes, and periods of active sleep occur about four times a night. Your baby’s sleep cycles are about half as long and involves twice as many periods of active sleep.
This all means that your baby spends a lot of time in rather light sleep, and can awaken easily during his initial period of dream sleep, or during transition into deeper quiet sleep. You will probably recognise the well known phenomenon of thinking your baby is fast asleep and deciding to carefully ‘extract’ him from your neck or put him down in his crib, only to see two eyes looking at you, followed by your baby waking up properly and protesting to your actions. To get around this, it may be best to a) wait a little longer until he has reached deeper sleep, or b) (when he’s a little older) put him down drowsy but not yet asleep.
From around 3 months your child will enter NREM sleep first (like you do), moving rapidly through the quiet sleep phases into deep sleep. However, the length of her sleep cycles will not reach 90 minutes (like adults) until around 3 years.
3. What Are Dreams Made of?
We dream during the stage of REM (Rapid Eye Movement) sleep. During dream sleep, there is an increased blood flow to the brain, and scientists suggest that this supports brain development. Studies show that REM sleep stimulates the brain regions used in learning, which indicates the importance of dream sleep for a developing brain.
Research shows that a fetus has almost 100% REM sleep, which would support the theory that dream sleep supports brain development already when the baby is still in utero. It seems that the body provides more REM sleep in the womb and during the first three months of infancy, which is when brain development is most rapid. A newborn up to about three months experiences 45-50% REM sleep. Brain development slows down as the child grows, which means that less REM sleep, or dream sleep, is required. A two-year old toddler spends about 25% of sleep in dream stage, and by about three years of age the time spent in active dream sleep decreases to about 20% (similar to adults). Further evidence to support the importance of dream sleep in a developing baby is that premature babies can have as much as 75% REM sleep (their initial development outside the womb was supposed to happen in utero.
4. Developing a consistent sleep pattern
You will find that life with your newborn means following her cycle of needs – as well as soothing and cuddling her, you will be making sure she has comfortable clothes, that she gets interaction and stimulation for development, and that she has been fed and had a nappy change before she is ready for another sleep (not necessarily in that order). And the time she stays awake often doesn’t last long. Most things will be tiring to your baby because everything is new and needs to be taken in and processed. Your newborn can sleep up to 18 hours a day, and this happens in nap-sized bites of between 2-4 hours at a time, ‘round the clock. As your baby still has not yet learned to follow a day/night pattern (circadian rhythms), she will be governed by waking up when she needs a feed. And with a small stomach, feeds are small and frequent. You may start to see the development of a clearer sleep pattern from 3 months onwards, but it may take up to 6 months for it to become consistent.
The Beats of the Circadian Rhythms
Circadian rhythms are physiological changes in the body that follow a 24-hour cycle. Many of these physiological changes are influenced by daylight and exposure to sunlight every morning helps maintain our ‘internal clock’ (natural signals around when to sleep and eat). During the day your body produces more cortisol, which is a hormone that keeps you alert. Into the evening and as it gets darker, less cortisol is produced and instead more melatonin is produced (melatonin is a hormone that makes you drowsy).
Babies’ sleep are not governed by circadian rhythms in the beginning, as this doesn’t develop until they are 3-4 months old. And it can take up to 6 months before your baby starts sleeping through the night (which tends to be defined as sleeping a nightly stretch of 5 hours).
Research has shown that while in utero, babies share a hormonal connection with their mothers, and are therefore picking up on the more active daytime and the slowing down during night-time. In particular, mother’s melatonin (night time hormone) passes through the placenta, and baby’s heart and respiratory rates slow down when mother is sleeping (and speed up when she is active). During pregnancy, fetuses are tuned into their mothers’ physiological cues about day and night. Fetal heart and respiratory rates speed up when Mom is active and slow down when she is sleeping But after birth, this intimate hormonal connection is broken, and newborns must rely on their own internal clocks.
Once born, your baby can no longer rely on mum’s hormonal regulations, and has yet to develop his own circadian rhythms. Although you may start to see an early response to the natural cycles of day and night, your baby will only start showing a more consistent day/night sleep pattern from about 3 months or older. The production of the "sleep hormone” (melatonin) shows at about 3 months, while the "waking hormone” (cortisol) shows ‘circadian changes’ (following a day/night cycle) even later.
So is there any point thinking about a routine early on? Well, babies are busy adapting to what is happening around them, and research tells us that they are receptive to the cues we provide around differences between daytime and night-time. Therefore, it can be helpful to start helping your baby to adapt to a day/night pattern early on. (Find tips in Sleep Angels).