by Anya Dunham, PhD
Why do babies fight sleep? Actually, they don't; they work on developing sleep rhythms and connecting sleep cycles to begin sleeping soundly when they are ready… unless we interfere.
Have you ever paced the room with your baby in your arms, thinking “Why is she trying so hard to stay awake when we are both exhausted? She needs sleep, it’s good for her… Why do babies fight sleep?”.
However, science suggests that babies don’t actually fight sleep (even though it might seem like it!).
Here are 3 reasons your baby appears to be fighting sleep, along with 3 things you can do about it:
Most babies come into the world falling asleep easily. Newborns have high levels of melatonin they received from mom before birth. This melatonin keeps them extra sleepy most of the day and night.
After that first sleepy week, the borrowed melatonin dissipates and “day-night confusion” often sets in: baby begins sleeping in short stretches around the clock or sleeps more during the day than at night. His circadian rhythm has not yet developed, so he goes to sleep when he’s tired but wakes up as soon as his drive to sleep diminishes, taking naps at all hours.
Between 6 and 12 weeks he will begin to make melatonin himself, but the levels will still be low.1 His developing sleep rhythms may not be in sync with each other: waking and sleeping states may overlap, be incomplete, or switch rapidly. Wakeful but tired, baby may cry a lot. Some researchers believe that immature sleep rhythms and the resulting tiredness are one of the major reasons for the inconsolable crying we know as colic.2
You probably know that all of us tend to wake briefly between sleep cycles and become more aware of our environment. If all seems well, we turn over, peacefully return to sleep, and most likely don’t recall this brief waking when we get up for the day. In other words, we connect our sleep cycles smoothly.
Babies wake briefly between sleep cycles as well, but they may or may not go right back to sleep. So, night wakings themselves are not a problem and are completely natural. Most restless nights are due to difficulties getting back to sleep, or re-settling, after waking.
Did you know that most babies are capable of re-settling to sleep on their own when they are very young? In one study, 1-month-olds re-initiated sleep on their own in one out of every three night wakings.3
But when scientists followed babies through their first year, 57% gradually began sleeping better by re-settling on their own more, but 43% re-settled on their own less over time.3 Why did some babies develop this ability further while others seemed to have forgotten it?
Because we are shaping our babies’ sleep no matter what we do.
Whether you actively soothe your baby to sleep or your baby goes to sleep on his own, he learns to recognize it as a pattern. Swaddling, rocking, nursing, pacifier, bottle, swing, car seat, Daddy’s arms… through these experiences our babies learn how to go to sleep and return to sleep.
Babies wake when they are hungry, wet, or unwell – in other words, when they have a need greater than their need to sleep. But they don’t wake up because they want to bounce on an exercise ball, swing in their swing, or go for a car ride… they wake because they established a sleep association and now need it to go back to sleep.
They want to go back to sleep.
And that’s why they are crying or fussing – not because they are fighting sleep.
When we create sleep associations that are not sustainable for us and not necessary for our babies, no one sleeps well.
And it looks like babies are fighting us.
Many older babies who have been sleeping well begin waking more at night or taking longer to fall asleep at bedtime around 8 or 9 months old. What is happening?
(It’s unlikely to be teething - see #6 on this list of cool baby facts)
So why do babies appear to fight sleep at around 8 or 9 months old?
First, they are working hard and once again may need extra time to wind down. They are going through many developmental leaps: learning to crawl, stand and perhaps even walk; trying a variety of foods; rapidly expanding their repertoire of sounds.
Second, they are beginning to understand complex sequences and not only see that certain events tend to follow one another, but also realize that they can make things happen (for example, they can put one block on top of another — or call Mommy and make her appear!). If your baby sleeps separately from you and is used to drifting off to sleep calmly on his own, he may now protest when you leave the room.
Finally, most 8-month-olds have moved to napping twice a day. If they’ve been going to bed a bit too late or napping on the go, overtiredness may be catching up to them.
I bring together the science of baby sleep and offer a stage-by-stage guide in my book, Baby Ecology.
1. McGraw K et al (1999)The development of circadian rhythms in a human infant. Sleep 22(3): 303-310
2. White BP et al (2000) Behavioral and physiological responsivity, sleep, and patterns of daily cortisol production in infants with and without colic. Child Development 71(4): 862-877
3. Burnham MM et al (2002) Nighttime sleep-wake patterns and self-soothing from birth to one year of age: a longitudinal intervention study. Journal of Child Psychology and Psychiatry 43(6): 713-725