April 24, 2024

The Four-Month Sleep Regression and How to Survive It

Babies, Newborns

Did the mere title of this post make the hairs on the back of your neck stand straight up? Those who have heard of the four-month sleep regression dread those words.

I still kind of shudder, both from my personal and professional experience when I hear it, because I know how hard the four-month regression can be!

While the physical changes that occur in your baby around the four-month mark aren’t avoidable, we can avoid some of the tougher after effects. I am certainly not saying you’ll skip the four-month sleep regression altogether, because that’s usually not true.

But I am saying you can more confidently navigate the four-month sleep regression and come out on the other side with sleep!

So in this post, I am going to share:

  • What the four-month sleep regression is and why it happens
  • Signs your baby is experiencing the four-month regression
  • How long the four-month sleep regression usually lasts
  • How to help your baby get through the four-month regression

And more!

What is the four-month sleep regression?

The four-month sleep regression is an actual, physical change that happens to your baby’s sleep. Newborn babies’ sleep is underdeveloped, meaning they only have two sleep cycles – they spend half of their time in a deep sleep and the other half in lighter sleep and they just flip-flop between the two.

Around four months old (it might be a little before or a little after), babies’ sleep starts transitioning into more developed, adult-like sleep cycles. Rather than just having two sleep cycles, they now have four.

This is a big change for babies because more adult-like sleep cycles mean more time in a lighter stage of sleep, which babies aren’t used to.

What does the four-month sleep regression look like?

The most common signs of the four-month sleep regression are an uptick in night wakings and short naps. Because babies are now adjusting to more time in a lighter stage of sleep, it’s like they start “falling out of sleep” and need help getting back to sleep.

The four-month regression can also be characterized by what feels like a never-ending bedtime. You rock your baby or feed your baby to sleep per usual, you lay them down, and the moment they touch the crib, their little eyes pop open and you have to start all over again.

That’s because these adult-like cycles also mean the “drowsy but awake” strategy that often works to help get newborns to sleep no longer works! Now “drowsy” is essentially the first step of sleep, just like it is for you and me.

So when you lay your baby down drowsy, or just asleep, that drowsiness gets disrupted, they wake up, and you have to start all over again.

We experienced this so vividly with our oldest. She was a great sleeper as a newborn, but around four months old everything went downhill, and we had never even heard of the four-month sleep regression.

She went from waking once a night to waking 4-7 times a night, and no matter how many times she would wake up, I would immediately nurse her and then burp/rock her to ensure she was fast asleep, and then lay her down.

That then became our pattern and remained so until she turned 10 months old and we finally sleep trained her!

I became a sleep consultant right before my second daughter was born, so our whole experience with her sleep was different.

I remember her four-month sleep regression vividly because we had just moved into the basement of our friend’s house. Avery started sleeping through the night around 10 weeks old, which is definitely not a norm or expected, but it was wonderful.

But that night we moved in felt like we had a new newborn all over again – she woke up a lot. I tried getting her back to sleep a few times, but out of survival mode and also being nervous about waking up our new housemates, I held her the rest of the night. It was brutal!

I don’t remember super clearly, but I think she really only had one rough night, and the other nights were back to much more normal. I also got more comfortable waiting before responding in the night, giving her a chance to fall back asleep first, because now I knew our friends upstairs couldn’t hear her.

Finally, with our youngest, we pretty much slid right through the four-month sleep regression, unscathed. The only reason I knew she was technically going through the “regression” was because drowsiness started impacting her bedtime – it was taking her longer to fall asleep and she fussed a lot more.

So I just got intentional about avoiding that drowsiness while nursing her, and she was back to her normal self! No extra night wakings, no shorter naps, nothing.  

All of that to say, the four-month sleep regression will likely look different from baby to baby, but regardless of how exactly it looks, a physical change is happening.

Curious to learn more about the sleep foundation we were able to lay with our younger two girls that made the four-month sleep regression much more bearable? Our newborn sleep class, Newborn Sleep from A to Z, walks you through everything you need to know about your newborn’s sleep, as well as how to actually lay that same foundation, for babies 0-16 weeks old.

How long does the four-month regression typically last?

As a general rule of thumb, sleep regressions typically last around two weeks, and this is true of the four-month sleep regression, as well. It might take a solid two weeks or so before your baby’s sleep cycles have fully adjusted.

The reason many families think this regression lasts a lot longer is that we tend to enter survival mode when sleep goes haywire. We do whatever we can to just get our baby back to sleep so we can get back to sleep.

With our oldest, that meant each time my baby woke up, I nursed her and rocked her back to sleep, however long it took and however many times it happened. Did she really go from just needing one night feed to needing four? No! But that was the quickest and easiest way for me to get her back to sleep, so that’s what we did.

The problem was, she quickly learned that the only way to get back to sleep in the middle of the night was to nurse. So even after the technical “two weeks” of the regression were up, nothing changed – she was now in the habit of stirring, then fully waking, then nursing back to sleep, repeat.

Strategies to Help Your Baby Get Through the Four-Month Sleep Regression

Now let’s talk about how to survive and thrive through the four-month sleep regression…

1. Wait Before Responding

Remember how I mentioned you’re little one might be “falling out of sleep” more during the four-month sleep regression? If you hear your baby wake up in the night, try to wait before responding. Try to wait for about 10 minutes, if you’re comfortable. We always want to give them a chance to fall back into the next sleep cycle before going in there and helping.

Yes, your presence will certainly be comforting, but they could also become more stimulated with you in there, so we always want to give them a chance to fall back asleep first. Then, if you’ve waited and they haven’t calmed or fallen back to sleep in those 10 minutes, then go in and help them back to sleep.

This is what we didn’t do with our middle daughter, out of fear of waking up our housemates, and I bet if we had just fully waited, that awful night would have looked a bit different.  

2. Help Your Baby Back to Sleep in Different Ways

If your baby was eating once or twice a night before the four-month sleep regression, they should not all of a sudden need to eat four+ times! Babies do often go through a growth spurt around four months old, so if they’ve only been getting one night feed and now seem to need two, that’s reasonable! But they very likely don’t need more than that.

As a general rule of thumb, if it’s been around three hours or more since their last feed and you think they’re hungry, go ahead and feed them! If it’s not yet been three hours, however, and you’re confident they had a full feed earlier, try patting, shushing, or rocking them back to sleep. We don’t want them to think they need a feed each time, so use other strategies to soothe them back to sleep.

If you’re a breastfeeding mom, this is a good time to send dad in so your baby is not confused as to why you’re there but not feeding them!

3. Transition Out of the Swaddle and the Bassinet

Movement is such a big piece of learning to self-soothe, so we want to give babies the ability to do so! Your may want to sleep with their hands over their head, fist by their mouth, or along the side of the crib, and having the ability to figure out that sweet spot is so important!

For this reason, if your little one is still in a swaddle at four months old, it’s time to transition out. Even if your baby is not yet able to roll over, we want to give them the opportunity to move and learn how to get comfortable.

Similarly, if your baby is still in their bassinet, it’s time to transition to a pack ‘n play or their crib! We want to allow them to move around, and by four months old most babies are getting pretty big for their bassinet.

4. Consider Sleep Training

The exciting news is, four-month-olds don’t simply hit a sleep regression, they are also now at an age when they can more purposely use their little arms and body, which means they can learn to settle themselves to sleep.

So this is the age when we can officially start sleep training if that’s something you’re hoping to do!

And you don’t have to wait for the four-month sleep regression to be “over” to start sleep training, because it may not actually feel “over” until you make changes! While sleep training doesn’t help you skip the four-month sleep regression, it often does help you get through it more quickly, or come out stronger than when you first entered.

If you’re curious about what sleep training methods are out there and would be best for your baby, read this blog post!


The four-month sleep regression is unavoidable, as all babies’ sleep physically changes around that time. However, what the four-month regression actually looks like is different for every baby!

The good news is, the four-month sleep regression does not last forever. The above strategies will not only help you survive the regression, but they will also help you come out of the four-month sleep regression and continue moving toward solid sleep!

If you have a newborn, I want you to know there is so much you can do right now with your precious newborn to help lay a foundation for sleep so that when the four-month sleep regression comes, your baby has had practice falling asleep on their own! So when they “fall out of sleep”, it’s not so surprising to be alone and on their back, and they can try to get back to sleep.

OR, if you’re in the thick of the four-month sleep regression right now and just don’t know how to come out of it, or your baby is technically beyond the four-month sleep regression but sleep has been such a struggle since, Baby Sleep from A to Z is a great resource for you to make a plan for what’s next!

With Grace,