The Early Bedtime
You have probably read about it or heard about how an early bedtime is best for your baby and/or toddler. At this very moment you are thinking “ya ya I know!” but I am going to say it again, having a consistent early bedtime is one of the best ways to help your baby not only improve night sleep but also improve day sleep!
Before jumping into the actual bedtime talk I want to discuss the driving forces behind sleep! I feel this is important to understand why appropriate bedtimes are so beneficial.
Processes Responsible For Sleep
1. The Homeostatic Sleep Drive or Sleep Pressure: This is the easier concept to understand as sleep drive or sleep pressure means that the longer you are awake the greater the drive toward sleep. I like to say if we look at sleep drive/pressure like a battery then when we wake up the battery would be fully charged but as we stay awake and use energy the battery power diminishes until it is empty and this means it is time to go to sleep again! When we wake up we have a low sleep drive/pressure because we are rested but as we use our energy then our sleep drive/pressure or the need for sleep increases to restore our body!
This sleep drive or pressure builds very quickly in infants and toddlers and this is what allows them to have naps. Adults on the other hand take longer to build this sleep pressure and this is why if we are well rested then the pressure is greatest when we go to sleep for the night (unless we are sleep deprived parents and then sometimes this pressure is high enough during the day to sneak in a nap).
TIP: Even a 10 minute snooze in the car/stroller/carrier is enough to relieve the pressure just enough to make your baby fight their next sleep period.
2. The Circadian Rhythm: The circadian rhythm is controlled by our internal body clock. This clock determines many biological processes for our body and one of those processes is when our body is awake and when we are asleep. This would be referred to as a sleep-wake pattern. The internal clock is a part of the brain that signals the production of hormones that either keep us awake (adrenaline and/or cortisol) or make us sleepy (melatonin). The brain is told which hormones to produce based off of light-dark patterns. Light/day signals the brain to produce adrenaline and/or cortisol (awake hormones) and darkness/night signals the brain to produce melatonin (the sleep hormone). This is how daily sleep-wake cycles develop in our Circadian Rhythm. Our Circadian Rhythm is able to get into a pattern of when we will be going to sleep and when we will be waking up and this becomes your baby’s (and yours) sleep-wake cycle. As we get closer to bedtime the body signals the production of melatonin to rise to prepare for sleep and then in the early morning hours of the night the body starts to signal the production of adrenaline and cortisol to rise which will be what keeps us awake and alert come morning.
Now remember, babies have a sleep pressure that is building very quickly as well and so they also need to relieve this pressure during the day through naps. The circadian rhythm will also begin to identify patterns of when this sleep pressure is being relieved (1,2, or 3 nap schedules) based off of how long your baby can handle being awake for and we will again see little surges in melatonin to help have productive daytime sleep.
TIP #1: Darkness is what signals the brain to release melatonin and so during the day or if it is light at bedtime we need to make sure the routine and sleep environment are dim/dark to help this hormone production take place. This is why I stress the dark sleep room!
TIP #2: This is a biological process and not something you can really control. The body's sleep pressure and circadian rhythm are working together naturally and they need you (the parent) to work with them as well to keep your baby from becoming overtired.
ARE YOU BORED YET…..
The Early Bedtime
One of the best ways to help your baby improve night sleep, early mornings and bad naps is to have an early age appropriate bedtime. In most cases depending on your baby’ age, how many naps they are having and the quality of those naps this naturally falls between the hours of 6-8 p.m. It could possibly fall earlier than this in some cases but I always recommend to not have an asleep time later than 8 p.m. Now, although this seems like a wide gap it still allows for consistency while having room for flexibility based on the day your baby had. If your baby takes predictable naps that are typically the same length and at the same times then you are going to find that bedtime also falls around the same time each night but if your baby has an off day or skips a nap then bedtime will move earlier to make up for that lost daytime sleep.
TIP: Just because your baby has a bad nap day does not mean that they deserve total less sleep hours! Bad nap days usually lead to earlier bedtimes (maybe even earlier than 6 depending on the situation) so that their body can make up for that lost daytime sleep at the beginning of the night.
The Homeostatic Sleep Drive or Sleep Pressure has a huge role in bedtime because depending on your baby’ age there is only a certain length of time that they can be awake for in between sleep periods before that pressure needs to be relieved. These are called “wake times” and there are guidelines for what works best for different age groups. Younger babies have smaller wake times and then as your baby gets older the wake times become longer which corresponds to their body being able to go longer in between sleep periods before their sleep pressure needs to be relieved. This is how babies naturally go from a 3 to a 2 to a 1 to a no nap schedule. We want to use a developmentally appropriate wake time for our baby to determine what time they will be ready for sleep after their last nap. Every baby is a little different but here are some suggestions:
4 months: Baby to be asleep 1.75-2 hours after waking from last nap period.
5 months: Baby to be asleep 2.25-2.5 hours after waking from last nap period.
6-7 months: Baby to be asleep 2.5-2.75 hours after waking from last nap period.
8-9 months: Baby to be asleep by 3-3.5 hours after waking from last nap period.
10-11 months: Baby to be asleep by 3.5-3.75 hours after waking from last nap period.
12-18 months: Baby to be asleep by 3.25-4 hours after waking from last nap period. This one has more range depending on what that 2nd nap is doing for them!
** Again, these are guidelines **
** Younger babies usually fall on the shorter ends of the ranges above
** Once on 1 nap I find that using more set times is beneficial
The Circadian Rhythm plays its role in bedtime based off of bedtime being relatively consistent (except for the occasional off day when bedtime might be earlier). The body naturally is ready for sleep between those hours of 6-8 p.m. based on wake times and therefore the body will get into this pattern of preparing for night sleep around these hours. The body will be ready during these hours and so the wake time you use will fit perfectly into this pattern. The Circadian Rhythm is also based off the fact that generally between these hours it gets dark outside! Remember, darkness signals melatonin production.
TIP: If you live in a location where it stays light outside until late into the evening then you may need to have a 45-60 minute period before bed where you come in from the bright sunlight and start to dim the environment to help the body prepare for sleep!
It is important to keep both of these processes in mind when thinking about bedtime. A common “want” from parents is a later bedtime and although the circadian rhythm can be based off of patterns the sleep pressure is not. We need to respect both of these factors and have them both balanced in order for the body to get the most restorative sleep.
It is a natural or biological process for the body to be ready for sleep earlier in the night between 6-8 p.m. Sleep cycles are divided between Non-REM (deep) sleep and REM (light) sleep. When your baby falls asleep at the beginning of the night they will be experiencing longer spurts of Non-REM sleep in each cycle but as the night goes on the body slowly begins to experience more REM sleep. This is why going to bed earlier and waking up earlier is more beneficial than going to bed later and sleeping in later. There is more time spent in deep sleep during the first half of the night than there is the second. Deep sleep is the most restorative sleep.
The Bedtime that’s Too Late!
Alright, so now we know that we need to have a balance as outlined above but in many of the cases I work with bedtimes are still too late. A common occurrence is bedtime falls between 6-8 p.m. which is good except the wake time before bed is way too long and therefore the baby is overtired! For example, your baby is going to bed at 7:30 which is between those hours of 6-8 but going by their wake time from when the last nap ended the asleep time should have been at 7:00. This makes a really big difference.
Let’s go back to the hormones adrenaline, cortisol and melatonin for a minute because it comes down to what these are doing when your baby is staying up too late or past their window of sleep opportunity (appropriate wake time).
As your baby approaches the end of their wake time the body is increasing the melatonin (sleep hormone) production so that when it is time for sleep we have a nice big build-up of the wonderful sleep hormone to make your baby fall asleep faster and stay asleep longer. If bedtime gets pushed back later (in many cases 15 minutes or more) then your baby’s body is going to respond to this through a ‘fight or flight’ response. The fight or flight is a stress response to a situation that may pose a concern to the body. In terms of bedtime being pushed too late the body is ready to be sleeping based off our developmental wake times but if we do not go to sleep then the body assumes that there is a reason for it or a problem and so it signals a burst of adrenaline to help the body stay awake to solve the problem. This is called getting our “second wind.” At this point the melatonin production has been suppressed and your baby will be ready to go which also means they will be fighting sleep a lot more at this point. The adrenaline increase is also paired with a cortisol increase which is our “stress” hormone and impacts sleep similar to that of adrenaline.
Adrenaline and cortisol are meant to be hormones that help your body be active and awake during the day and so when they are released at night it makes it very difficult for you to soothe your baby, for them to soothe themselves, fall asleep, stay asleep and stay asleep in the early morning hours. This is why babies who go to bed too late fight sleep, wake up more frequently in the night and wake up earlier in the morning. This is also why if you put your baby to bed later they will not necessarily sleep in longer in the morning and more often than not the opposite actually occurs and they wake earlier.
The vicious overtired cycle: Your baby's bedtime is pushed too late which signals the fight or flight response. This response causes more of a fight at bedtime, more night wakings and/or an early morning. Now your baby is tired right from the get go because they didn't get as many sleep hours as they needed in the night and so the fight or flight response may occur before the first nap which in turn causes a short nap. Then they are tired from that short nap and so the stress response occurs before the next nap. This continues until bedtime rolls around again and baby is ready for an early bedtime but gets put down a little too late again. The cycle repeats! It all starts with bedtime :)
TIP: As parents we want to try and prevent this fight or flight response or prevent our baby from becoming overtired as much as we can so that their sleep is not interrupted.
Is my Baby Going To Bed Too Late?
Do they appear to get their second wind following looking tired in the evening?
Are they fighting you to fall asleep even with all of your best soothing techniques?