Over the years, our team has seen countless parents come to us for help with their 4 month old babies sleep. Why? Simple – it’s the 4 month sleep regression. This article will explain why “good” sleepers sometimes turn “bad” around the 4 month old mark, also known as the 4 month sleep regression. For most babies, the 4 month sleep regression occurs right around the 4 month mark, but for some babies, it happens a bit earlier (around 3 months) or a bit later (around 5 months). For some babies, the 4 month sleep regression is relatively mild and very brief; for others, the 4 month sleep regression is a very, very rough phase marked by lots of crying, and that lasts pretty much indefinitely.
4 Month Sleep Regression: How Your Newborn Baby Sleeps In The Early Weeks
Yes, this is an article about the 4 month sleep regression, so we really should be talking about 4 month old babies, right? We will, in just a moment – but first, we need to back up to the newborn phase. When a newborn sleeps, she cycles between “active” and “quiet” sleep (also known as REM and non-REM sleep), but does not have the distinctive stages of sleep she will have as she grows older and her brain matures. We’ll avoid too much technical talk (that’s one reason we have this website, so you won’t have to learn the whole history of sleep if you don’t want to (or can’t stay awake to!), but if you are interested in knowing more about our biological rhythms and how we do sleep in more detail, I highly recommend the book, Solve Your Child’s Sleep Problems), even if you have no interest in “Ferberizing” (just skip that part and consider a no-cry method). Newborns spend a lot of their time in deep sleep, which is why it is hard to wake them up (even to eat!) in those early days, but they do startle when they cycle into “active” sleep, which is one reason swaddling your baby can be so effective.
The 4 Month Sleep Regression Changes Things: How Your 4 Month Old Baby Sleeps (And Sometimes Your 3 Month Old Baby, or 5 Month Old Baby)
We all go in and out of light and deep sleep. As adults, we might change positions, look at the clock, or re-position our pillow. Up until now, you may have rocked your baby or simply given him a pacifier and he slept for hours without waking up. Well, at 3 or 4 months old, your baby is now sleeping more like an adult. Now when she falls asleep, she does not enter deep sleep right away, and if you lay her down before she is in deep sleep, she is likely to wake up and you will start all over helping her to fall back to sleep again and again.
4 Month Sleep Regression Patterns: First, Your 4 Month Old Baby Enters Deep Sleep…
Initially in the night, your 4 month old will enter deep sleep relatively quickly, within 30 minutes (this changes as we get older). However, as I said, we all cycle in and out of light and deep sleep. A child’s sleep cycle is about 40-50 minutes. So, your baby will briefly awake 40-50 minutes after she has been asleep. To put that in perspective, if you are holding your baby to sleep, you would need to hold her for at least 30 minutes to make sure she’s in deep sleep and then she might wake up 15 minutes later. Sound familiar?
Overall, though, your baby’s deepest sleep is in the early part of the night, so after that first sleep cycle, she might sleep just fine for a few hours. So, you’re golden, right? Just hold her for an hour? Nope!
4 Month Sleep Regression Patterns: How Your 4 Month Old Baby Sleeps The Rest Of The Night…
The technical definition of “sleeping through the night” is 5 hours of continuous sleep (i.e. no feedings) and many babies can/will do this by 2 or 3 months old. The beginning of the night is your baby’s deepest sleep, and after the first 5 hours (if not sooner, depending on just how challenging he is), he will cycle between light and deep sleep, but the deep sleep won’t be as deep as it was at the beginning of the night. This is where the problem of sleep associations really come into play. If your baby needs your help to go to sleep at the beginning of the night, sometime after midnight or so, he will continue to need your help every 1 or 2 sleep cycles (that means every 40 to 90 minutes, or as I often hear: every 1-2 hours).
Between 4-6 a.m., approximately, is the lightest sleep of the whole night (parents’ complaints alone make this true, in my experience, aside from my reading). In the very early morning hours (about 30 minutes to an hour before waking up), he will again go into the very deep sleep.
Although babies commonly wake up early, be sure it is truly their waking up time and not just this lighter sleep and that they are having trouble sleeping. You might notice they want a “nap” just 30 or so minutes after “waking up”. What you experienced was a night waking, not starting the day.
4 Month Sleep Regression Symptoms
Many parents want to know what the 4 month sleep regression looks like. That will vary from baby to baby, of course, but here is a short list of 4 month sleep regression signs:
- Changes in appetite (baby may eat more or less than usual)
- Lots of night wakings (these will seem out of the ordinary, especially if your baby had been sleeping longer stretches recently)
- Increased crying and fussiness (often, the fussiness will be the inconsolable kind, and nothing you do to comfort your baby will work as well as it usually does)
- Missed naps and/or shorter naps
4 Month Sleep Regression Explained
As we’ve established, all babies go through these changes in their sleep patterns. However, how your baby reacts to these changes will depend on unique factors. Some babies experience a week or two of fussy, interrupted sleep, and then go back to sleeping soundly at night and taking restorative naps. Other babies, however, are thrown all out of whack by the 4 month sleep regression, and they go through weeks and weeks (sometimes even months) of lots of night wakings and missed naps. These babies (and their poor parents!) are hit hard by the 4 month sleep regression, and exhibit a lot of the symptoms mentioned above.
So, if the 4 month sleep regression truly is a bad sleep regression for your baby – how can you cope? Well, we generally advise parents to get to the root of why the 4 month sleep regression is causing such disruptions. Usually, negative sleep associations are to blame – babies who have become accustomed to being rocked or fed or held to sleep continue to need their sleep associations, only now that their sleep patterns have changed, they need them all night long. Of course, mom and dad can’t sustain all that rocking and holding in the middle of the night, and so soon, the whole family is exhausted and overwhelmed. That’s usually when we hear from parents asking for a Personalized Sleep Plan™.
In general, I’d recommend waiting a few weeks, to see if your 4 month old baby’s sleep improves. If it doesn’t, then it may be time to make changes, and to work on weaning your 4 month old from his sleep associations. You might also want to work on establishing a gentle 4 month old baby schedule. I would urge you not to wait indefinitely, though – I talk to parents of 8 month old and even 20 month olds who are still waiting for their “baby” to grow out of their sleep problems.
For more tips on how to cope with and solve your baby’s 4 month sleep regression problems, you can read our other 4 month sleep regression article: The 4 Month Sleep Regression: What It Is and How To Fix It.
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Want more information about how to help your 4 month old sleep well? Check out our detailed case study about Nadia, Brad, and their 4 month old, Abigail.
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Sandra says
It’s 530am & I’ve been struggling to get my 4 month old back to sleep for the last hour & half. He’s has scheduled feeding times during the day but not overnight & is exclusively breastfed. By 2 months old, he was able to sleep 5 to 6 hours before getting 1 overnight feeding around 3am & would go back to sleep. Shortly after 3 months, his sleep pattern changed where he would wake up consistently around 1am, 3am & 6am but would only be fed at 3am. At both 1am & 6am I was able to use a pacifier to get him back to sleep in about 5 minutes. In this past week, his overnight pattern is still the same but the biggest difference is now he won’t fall back asleep even with the pacifier. Sometimes I let him cry for 5 min before burping him & giving him some water while still in his crib. Interestingly while he’s sitting up he doesn’t cry but the second I lie him back down he cries. Though I can calm him down with his pacifier & favorite toy to the point where he almost asleep, he seems to wake up 5 minutes later making it a viscious cycle. I feel horrible in that I have to tell my other half not to pick him up to soothe him to sleep or bring him to our bed, as I know it will only start a bad habit that I will need to break. Help! I’m not sure if the issue is I’m letting him fall asleep for the night while breastfeeding.
ivana says
You ladies need to read Dr. Sears! And co-sleep, also do t cry it out! It actually harms baby’s emotional growth! They cry because a need has to be met, if you let them cry without meeting that need they will lear that they can’t trust their caregivers to respond and will stop crying
So it might seem to you that it has worked, but truly it hasnt. Babies this young should not left be alone to fall asleep, they need help with that. I Co slept with my first for a year and I currently co-slerp with my four month old. My first I tried putting g her a crib at 3mos but she slept horribly. She slept best cuddled up beside me, same goes for my son. And I don’t think pacifiers are a sleep association, sucking is a means of comfort for small babies, and pacifiers provide that. My first had a pacifier but gave it up just after a year old, no issues. We need to stop pushing our tiny babies to be so independent and stop trying to get them to fall asleep on their own and stay asleep. They need us alot and its our jobs to meet those needs,no matter how tired we are.
Nicole says
@Ivana Thanks for commenting! I’m so glad you found what worked for you, but I do want you to consider that what worked for you does not work for everyone. It’s great you were able to successfully co-sleep, but for some of us, it just doesn’t work out that well. I was hyper-sensitive I’d roll on top of him or cover him with a blanket or my husband would roll on him, etc. It was not the best sleep, yet better than getting up every 2 hours. However, long-term, it just wasn’t a solution for us. I respect you disagree that pacifiers or breastfeeding all night (human pacifier) are not sleep associations and it’s great that yours gave it up with no problems at one year, but, again, that is not always the case and some wake for a pacifier replacement ALL night. You, personally, may be able to function on waking every hour (though it doesn’t sound like that happened to you) but others can’t function or become ill more frequently, etc. Again, you might want to keep in mind that what you live day-to-day is not what others live day-to-day and try not to judge others for the decisions they need to make for their own families. Thanks again for sharing what worked for you!
cindi says
My 16 week old suddenly went from sleeping 8 hours a night to sleeping a four hour stretch (10 PM – 2AM) then a two hour stretch ((2:30 – 4:30) and then I need to wake her up to go to daycare at 6:30. I was getting really frustrated so I am glad to see that this is normal. I also feel extremely luck that it is only 2 times a night that I have to get up with her not five or six. That would be really difficult to do that and then have to go teach a class room of middle schoolers all day.
Lynda Bishop says
now following you~~ Pls enter me in contest USA
Jenell says
So I don’t think we has hit sleep regression till last night. She will be 4 months tomrrow and she was up every hour or half hour at a time. She just has to work through this right? Sorry only going 3 hours of sleep just hoping this gets better quick.
Jenell says
My lo will be 4 months the 18th. She already wakes about 15 mins to half hour after being put down. Shes been doing this since about 3 months. I typically rock her or hold her and pat her butt till she falls asleep. does this mean shes already going through sleep regression? she will after finally asleep sleep between 4-7 hours then wakes up rooting to nurse then asleep again for another 2 to 3 hours. when she wakes to eat she never fully wakes up but eats a full sitting then lets go and goes back to sleep. Would this already be considered it? also I have tried to get her to sleep earlier. Once in a while she will fall asleep at 8 or 9 but usually she doesnt fall asleep till 1030 or 11pm. she will wake up for the day at around 8am like clockwork. then asleep about an hour or 2 later for her nap. Im wondering if I need to shorten her late nap or wake her up earlier? Help would be great. Thank you.
Debbye says
Hi Jenell,
It does sounds like 4 month sleep regression and some sleep associations, and this age can often be a difficult one with regards to baby sleep. We don’t usually recommend sleep training until a baby is at least 4 months old and often most babies are not ready until between 5-7 months of age when they have gained a better ability to learn how to self soothe, which is a key skill to them learning how to go to sleep and stay asleep on their own. It is a good idea to works towards feeding your baby at night but not feeding her completely back to sleep. Allow her to finish eating and then lay her back down drowsy but awake, and not rocking or patting all the way to sleep too, so she starts to learn to fall asleep on her own.
Here is a link to our article with the recommended daytime, nap, feeding and bedtime schedule for a 4 month old. You may find it helpful in determining a good schedule for your daughter. Babies tend to wake at the same time in the morning regardless of what time they fall asleep at night, and I would recommend trying to get her bedtime much earlier. Some babies can not handle living on a schedule quite yet, but you can try to move her bedtime earlier by 15 minutes a night.
https://www.babysleepsite.com/schedules/4-month-old-schedule/
And you may find these articles about newborn sleep to be helpful to you now and as a part of starting to teach your daughter good sleep habits too.
https://www.babysleepsite.com/newborns/newborn-sleep-schedule-patterns/
https://www.babysleepsite.com/newborns/newborn-sleep-baby-tips-10/
Good luck!!!
anthony oni says
thanks for all the advice debbye.i’ve recently discovered that even all the preparations to put him to bed according to schedule have been unsuccessful.he finds it difficult to get back to sleep even when changing positions while sleeping.he hardly naps beyond 20-30 mins during the day, and wakes up at least 7-9 times at night for a minute’s meal of breast milk only to wake up an hour later. im live in nigeria and i’ve wondered if the schedules will apply to own way of life here?
Debbye says
@ Mel- The good news is that sometimes she does only wake once in the night, this is good! Some babies take longer than others to learn to self soothe, up to 5-7 months or even more. So it sounds like you are on the right track. If you are concerned with sticking with this method, then feel free to change it up a little, going in and checking every 5-10 minutes and you can stay with her too if leaving her to cry is too much for you! Good luck!
@ Anthony Oni- Try to stick with your schedule for another week or so, but some babies do have a hard time getting on a schedule until they are a little older. You can try to teach him good sleep habits now by not letting him nurse all the way back to sleep when he wakes every hour. I am sure that Nigeria is different from California where I live, and you can definitely make a schedule that works for you and you life. It may just take a little longer for your son’s sleep patterns to mature and for him to be able to sleep in longer stretches.
Good luck!!!
Mel says
Thanks Debbye. I have spoke with the doctor and health visitor, she’s still gaining weight (not at the same rate she was before) but as long as she’s gaining weight they are not concerned, they’ve just told us to keep checking her weight every 2 weeks to make sure she’s still gaining.
Some nights she wakes up only once for a feed other nights she can wake up 3-4 times (but only wanting a feed one of those times). We have started to leave her crying when we know that she isn’t hungry or needs nappy change and she does eventually go back to sleep but she can be up to 30mins to 1 hour crying. I don’t want to stick to this method if it’s not going to work. I really hope that I’m doing the right thing.
Mel says
My 4 and half month old girl was sleeping through the night up to 6 weeks ago. She used to sleep from 10.30pm when she had her last feed until 6 to 7am. Then she would feed every 3 hours and have regular naps lasting between 1 to 2 hours each. She could not stay awake for longer than 2 hours. She would settle herself to sleep and only sometimes I would need to give her a dummy to help her. But 6 weeks ago she started getting really grumpy, not feeding well and started to wake during the night and was not able to settle herself and it was a struggle for me to try and settle her too. She had a bit of colic so i started giving her infacol and that seemed to start helping after a week, then she got a cold and was poorly for a couple of weeks. She started getting better from her cold but was still very unsettled and not feeding or sleeping well. Anyway this week it has come to light she has been teething as i can see her first tooth coming through. I want to get her back to how she was before all this but just don’t know how! She used to be a real good eater but now I struggle to get 20 floz into her in a day (including night). Help!
anthony oni says
how do i get my 4 and half month son to sleep at least 4-6 hrs at night? he isn’t much of a day sleeper either. he wakes up every hour of the night and only goes back to sleep after sucking breast for a min.
i really pity the mum as she looks so exhausted every morning.
he used to wake up at most 3 times in his early infancy but everything has changed recentyl.