At some point, pretty much every new parent becomes obsessed with their baby’s sleep. How can I get my baby to sleep more? Longer? Better? To fall asleep without rocking, nursing, or bouncing?
An enormous number of books, blogs, and newsletters have been written on this topic. But as the volume makes clear, there’s no magic bullet. All baby sleep solutions require lots of effort, patience, and time.
That’s the bad news.
The good news is that while we have less control over our new baby’s sleep than we would like, we have more control over our own. Plus, the lessons of baby sleep can help us manage our own sleep. So let’s consider a few of the most important lessons.
1. Our bodies keep time.
We humans are diurnal. Unless we are working the night shift, we feel most tired right before bed and most awake in the morning and in the evening. (A post-lunch slump is also normal, and in many cultures corresponds to a late afternoon nap.)
But how do our bodies achieve this remarkable feat? How do we know when to feel tired, and when to feel awake?
Two distinct, brain-based biological clocks maintain our daily rhythm.
The first and best known clock resides in a tiny area area of the brain known as the suprachiasmatic nucleus (SCN) . It uses light to set our circadian rhythm, by releasing cortisol in the morning (making us feel awake) and melatonin at night (making us feel sleepy).
For shifting this clock’s internal settings, strategic sunlight exposure is the ultimate weapon.
Early morning light exposure shifts this clock forward to earlier wake times; late evening light exposure shifts this clock backward to later wake times. The same process–eventually–helps consolidate a newborn’s night sleep.
The second, less well known internal clock depends on wake time. After around 16 hours of wake time, this clock says enough is enough and starts making us feel sleepy.
Newborns also have a wake time clock, but it operates at a vastly faster clip than adults’. Newborns can tolerate very short amounts of wake time, usually only 1-2 hours, before becoming overtired.
Strategic sunlight exposure is the ultimate weapon for shifting YOUR INTERNAL clock’s settings.
Our babies’ SCNs are not set when born. Instead they calibrate slowly over the first few months of life. Fortunately, we, as adults, can speed up calibration by maintaining night environments (low light, limited interactions, limited eye contact) vs day environments (bright lights, stimulation, and interaction). As a friend of mine once scolded her husband, after catching him cooing it up with their newborn at 2 a.m., there’s no smiling at night.
2. Avoid the blue screen of death (for sleep).
Light, through primary clock #1, tells our bodies when it is time to wake up.
But for this purpose, not all light is created equal. Instead, light in the blue spectrum reigns supreme, by potently suppressing the sleep onset hormone, melatonin.
Before the widespread us artificial light, humans were exposed to blue light only when the sun was high in the sky. Nowadays, though, with smartphones, tablets, and computer screens, we are potentially exposed to blue light at any time of day.
Staring at your phone while nursing at night (so tempting!) can shutdown melatonin production–making it that much harder to fall back asleep once your little one does.
For breastfeeding moms, shutting off our melatonin production can rob of us another benefit. Melatonin passes into breast milk. This makes your baby feel sleepy when you do and helps them get on a normal night-day sleep-wake rhythm.
Staring at your phone at night can shutdown melatonin production–making it that much harder to fall back asleep once your little one Finally does.
Be sure your phones has the “night shift” option set, especially if you just can’t resist peeking at your phone in the evening or middle of the night.
3. Sleep begets sleep. And the bummer of a corollary: Lack of sleep begets lack of sleep.
You could call this the insomnia paradox: instead of making us sleepy, a lack of sleep makes it harder to sleep.
And as parents know, this is 200% true of babies. Overtired babies are notoriously difficult to get to fall asleep and stay asleep. Adults are the same.
We sleep better when we are well-rested.
When we are tired, our bodies produce counter-regulatory hormones like cortisol and adrenaline. These hormones help us stay awake and power through our day. But they can also overshoot their mark, making it harder to fall asleep when we are severely overtired.
We sleep better when we are well-rested.
Try to set a bedtime for yourself. Even if you know you’re “just gonna wake up in a few hours”, having a sleep schedule is good for you too. And find something calming to do in the 10-20 minutes before bedtime, whether it is meditating or doing a few slow stretches.
4. Beware (or at least be aware) of sleep associations.
It is an odd fact, but we (and our babies, after the first few blissful weeks of them falling asleep anywhere, in any position) do not just fall asleep when tired.
Instead, we learn to sleep. Specifically, we learn how, where, and when to sleep.
And we all know, babies form strong sleep associations. Put your baby to sleep by nursing? Your baby will likely want to nurse to sleep when they wake up in the middle of the night, whether they are hungry or not. Put your baby to sleep by rocking, bouncing, swaying? Your baby will demand the same movement to fall back asleep in the wee hours of the night.
While such “sleep crutches” are convenient and frankly necessary for newborns, as our babies grow older, these associations all too often end up haunting us.
Breaking these sleep associations is at the heart of the “no cry” versus “cry-it-out” controversy– approaches which hinge on teaching babies new sleep associations that do not require their parents waking up.
Although baby sleep associations are the five-alarm fire that new parents obsess over, we should be aware the we also have sleep associations.
Normal adult sleep associations are nowhere near as strong and rigid as a baby’s. So we tend to overlook them. But they can play a major role in insomnia.
Sleep experts now believe that harmful sleep associations are at the root of about 4 out of 5 cases of chronic insomnia. If you are suffering from insomnia, retraining sleep associations through cognitive behavioral therapy is a better first line approach than relying medications or alcohol, which sedate you but do not recreate natural sleep; in fact, they worsen sleep fragmentation and leave you feeling tired the next day.
we learn to sleep: how, where, and when.
Make your bed for sleep, and only for sleep. Do not get into bed until you are tired. Do not do anything else in your bed than sleep–no late night internet browsing or early morning emailing. If you wake up in the middle of the night and find yourself unable to go back to sleep. Get out of bed, and sit somewhere in dim light, reading or listening to a audiobook until you are ready to try to fall back asleep.
5. “Sleep when your baby sleeps” is obnoxious but good advice (that most of us can’t follow), but for sure don’t eat when your baby eats.
The two major brain-based internal clocks already mentioned are the big kahunas for maintaining our circadian rhythms. But humans have a bunch of secondary clocks in other bodily organs, especially those involved in digestion, like the liver, gut, and pancreas.
Like the primary clocks, these secondary clocks also produce a 24-hourish rhythm. But, unlike the primary clocks, their timekeeping depends not on light or awake time, but on when we eat.
So if we eat only during active daylight hours, these secondary clocks match up with our primary brain-based clocks. And this coordination helps us fall asleep and wake up at around the same time each day.
But when we eat right before bed or during our normal sleep hours, we muck with the coordination between our primary and secondary clocks–making it harder for us to fall asleep and stay asleep.
In addition to these benefits for sleep, restricting eating to daytime hours can help you lose weight, reduce blood sugar, raise insulin sensitivity, and increase basal metabolic rate. Eating late in the evening or in the middle of the night does the opposite. It also causes us to gain weight even without taking in extra calories.
secondary clocks HAVE 24-hourish rhythm. But unlike the primary clocks, their timekeeping depends not on light or How long we have been Awake, but on when we eat.
Find a non-food based way to unwind after your baby or older kids fall asleep. It’s hard to give up late night cookie or ice cream habit but it will pay back double relative to cutting calories earlier in the day.
6. Sleep cycles matter.
Everyone, even newborns, has sleep cycles, during which we pass through several stages of distinct brain wave patterns that fall into two main types: REM (rapid eye movement) and non-REM.
When adults fall asleep, we first pass through 3 stages of non-REM sleep. Each stage provides progressively deeper sleep. The third stage provides a deep and restorative type of Non-REM sleep known as slow wave sleep.
From there, adults enter REM sleep, a stage critical for memory consolidation and learning. After REM, we pass back into stage 1, starting the cycle all over again.
In adults, one full sleep cycle takes anywhere from 90-110 minutes, and we usually pass through 4 to 5 such cycles over the course of a night.
But as we pass through these cycles, they change. In the first half of the night, we spend the majority of our time in slow wave, or deep, stage 3 non-REM sleep. In the second half, we spend more and more of our time in REM sleep.
This fact may explain why most of us find disrupted sleep so debilitating. When we awaken on our own in the middle of the night, we tend to do so during light, stage 1 or stage 2 sleep, or while transitioning from one full sleep cycle to the next.
When we are awakened by our babies, however, these awakenings tend to occur during deep or REM sleep.
Then, when we fall back asleep, our sleep cycle has to reboot at stage 1. We lose out on the full amount of REM and slow wave sleep.
This fact may explain why disrupted sleep has such a profound impact on our mood and ability to think clearly, and often feels worse than just not getting enough sleep (such as when we sleep only 6 hours instead of 8 hours, for example).
When we are awakened by our babies, We lose out on the full amount of REM and slow wave sleep. This may Be why our disrupted sleep has such profound Negative impact on our mood and Ability to function.
While having a hungry newborn startle you out of sleep might be inevitable, you can make sure nothing else wakes you up unexpectedly during deep sleep. Take your phone out of your room or set to airplane mode before bed. Kick out your snoring, kicking, or comforter-stealing partner. Lock the cat out of the room. And see if your partner can take on one or two night feeds so you can get a longer stretch of uninterrupted sleep and a few full sleep cycles under your belt. And try to fall asleep soon after your baby goes down for the night. That first stretch of baby sleep is often the longest.
7. Sleep matters. A lot.
This is the ultimate lesson of new parenthood. Despite the many unanswered questions in the world of sleep research, the importance of sleep is not one of them. Contrary to common cultural messages suggesting we can “tough out” a lack of sleep, getting enough sleep is not a luxury; it is fundamental to our emotional and physical wellbeing.
Read on! Catch the next article in the series:
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- Park EM E al. Poor sleep maintenance and subjective sleep quality are associated with postpartum maternal depression symptom severity.
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