Updated: Aug 2, 2021
You've probably heard at least one mom say, "Eh, sleeping through the night is developmental. He'll just do it eventually." What does that really mean and is it true? Will children just start sleeping through the night at some point when they're developmentally ready?
What is "Developmental"?
First, it's important to understand what is meant by saying that something is developmental. This term is used to talk about a skill that naturally happens at a certain point in a child's development. For example, sitting up unassisted is a developmental skill. Babies usually do this around 6 months of age. A baby can't sit unassisted at 3 months because they simply lack the muscle tone and strength to do so; they're not developmentally ready for that skill. On the other hand, if a child isn't able to sit unassisted by, maybe 8 months, this may be considered a delay.
You can Google any developmental milestone to find out at about which age a child should have mastered that skill. Rolling, sitting, pulling themselves up, walking, talking...these are all developmental milestones that kids will reach around a specific age.
Parents and doctors can use these developmental milestones to track a child's growth and brain development and make sure it is on track. They are able to do this because these skills happen in a specific time frame or at least by a specific age. If there is a delay, the physician may want to do some tests to figure out the cause.
So, is sleeping through the night developmental?
Let me answer this question with a question:
If sleeping through the night is developmental, then what is the specific age at which this skill should be mastered by?
Remember, developmental skills have an average age at which they normally happen. I asked my Instagram followers what they thought the developmental age for sleeping through the night is. The answers were so varied: everything from 4 months to 1 year to "after they wean from the breast/bottle." So what's that say about sleeping through the night? It is not developmental. It won't just happen out of the blue someday when your child reaches a certain age. Sure, he's probably going to start sleeping through the night before he heads off to college. However, there is no specific age at which all children generally start sleeping through the night; therefore, it's not connected to a child's development.
I get clients ALL. THE. TIME. who tell me they just assumed sleep was developmental and their child would sleep through the night at some point. However, now the child is 1, 2, 3 years old and has yet to consistently sleep through the night. Why? Because sleeping through the night is not developmental.
What about Newborns?
One thing everyone can agree on is that newborns should not be expected to sleep through the night. Their stomachs are too small and, as a result, they need to eat frequently. They also have immature sleep cycles, erratic naps, day and night confusion, and their bodies don't start producing melatonin right away. However, all of the above is usually resolved by the age of 4 months. Their stomachs can now hold much more milk at a time. Their sleep cycles are maturing. Day and night confusion should be gone, and their little bodies are now producing melatonin to help them sleep.
Professionals in the sleep field will say that most children are developmentally able to sleep through the night somewhere between 3-6 months. So, if you do think that sleeping through the night is developmental, then 6 months would be the age at which your baby should have mastered it by. I actually know of some baby sleep programs that make you stop all night feeds after 6 months. Yet, we don't consider a child delayed if he isn't sleeping through by 6 months, so I rest my case that it is not a developmental skill. I've worked with so many older children who weren't sleeping through the night, but were otherwise developmentally on-target. (By the way, forced weaning at 6 months is not my approach to sleep training. I believe when taught the right sleep skills, the baby will give up the feed when ready- which is usually not long after we start!)
A Learned Skill
Sleeping through the night is a learned skill, not a developmental one. Yes, someone's friend of a friend may have a baby who just started sleeping through the night without any help. Yes, if you wait looooong enough, your child may eventually figure it out. Usually in these cases, the parents have sleep-trained their child without even realizing it. Yep, you read that right. Sleep training is not just letting your child cry for hours, as some may think. These parents may have been practicing good sleep skills with their baby or child and it eventually clicked.
For most babies and children, though, it might take a bit more effort. Learning the skill of sleeping through the night is like a big puzzle; there are a lot of little pieces that need to fit together in order for it to happen. Some babies/parents are able to figure out the pieces themselves, and others need to be taught how to do it through sleep training.
Sleeping through the night is a learned skill, not a developmental one. If you're waiting for your child to just start sleeping through the night on his own, you could be waiting a while. Sleep training (which does not have to be just leaving your baby to cry) is a way to teach your baby how to do this skill that he is already developmentally able to do.
Need help? Let's chat: sign up for a free 10-minute introduction call!
~Ashley Bell, your pediatric sleep consultant