What is the four month sleep regression, and what can I do about it?

Ahhh, the dreaded four month sleep regression. Yes, some people say that it’s not a ‘regression’ because it signifies a huge neurological development and is therefore an indication of a ‘progression’ as opposed to a ‘regression’. But let’s be honest here… whether you consider it a progression or a regression, it’s not easy! In fact, it’s more than not easy… it’s tough! Really, really, really tough for some – especially since it can last anywhere from 2 to 4 weeks (and up to 6 weeks for a few)! So let’s break it all down a little more and look at what’s actually happening…

What is the four month sleep regression?

Before a child reaches the four month sleep regression, they sleep in an entirely different way to how they sleep after going through the four month sleep regression. The changes that take place are tough to explain scientifically in one blog post, but I will simplify the details to fit as much in as I can…

Before the regression, a child doesn’t cycle in and out of sleep cycles like adults do. Because of this, children this age can often be put to sleep in a number of ways, be it feeding, rocking, shushing or bum-patting. They will then usually stay asleep until a need such as hunger becomes apparent, wake to be fed, and once again be put to sleep by feeding, rocking, shushing or bum-patting.

As a parent, this stage often feels ‘normal’ of sorts, as you expect to wake and feed your child a lot when they are so young. And once you’ve found your approach to put them to sleep, it works almost every time! Everything seems to be going well, with you being able to take them anywhere and sleep them anywhere. They also begin to sleep longer stretches at night, with some children even sleeping up to 12 hours each night! Until…

After the regression, and through a huge neurological development, a child now begins to cycle in and out of sleep cycles like adults do, except that an adult’s sleep cycle is 90 minutes long and a child’s sleep cycle is only 45 minutes long. So you will put them to sleep using your trusted feeding, rocking, shushing or bum-patting approach, hang out a load of washing, pour yourself a cup of tea, sit down to drink it and suddenly hear your child crying. What’s happened here? This child has cycled out of their deep sleep and entered light sleep around 45 minutes, and now requires your trusted feeding, rocking, shushing or bum-patting approach to help them transition to their next sleep cycle. Why? Because this is how they have always fallen asleep, and they simply don’t know any different. So because of this, a child can wake every 45 minutes day and night… and some do!

What can I do about it?

Use a Swaddle or Swaddling Product

Many children still have their moro reflex around this age, and because this reflex is most active during light sleep (the sleep that happens around 45 minutes, remember?), children can often startle themselves awake between sleep cycles and fail to transition to the next sleep cycle as a result. The other issue around this age is that children have often learnt how to break free from the swaddle. Parents often think that this means the child no longer ‘wants’ to be swaddled, however many children still need to be swaddled. If this is the case, it’s important to either find a more age-appropriate swaddling method, or to invest in a swaddling product.


Implement Bedtime and Naptime Routines

After the regression has passed, the children who continue to struggle with sleep are often the ones who associate sleep with the feeding, rocking, shushing or bum-patting approach that you have always taken. By implementing bedtime and naptime routines, you begin to create a new sequence of events which your child becomes familiar with, preparing them for sleep. With consistency, they will learn to associate sleep with the routine, helping them to wind down and make them less likely to resist sleep.

It’s important to find a routine that your child enjoys, that works for your family, and that you’re able to commit to doing every time. Some ideas may include a long warm bath, reading books together, and singing a lullaby.


Implement a Consistent Age-Appropriate Schedule

By implementing a consistent age-appropriate schedule, you help your child to avoid becoming overtired. When a child is overtired, they struggle to fall asleep and struggle to stay asleep. Feel free to use this table as a reference:

Child’s Age Time between Naps Number of Naps
Newborn to 1 month 45 minutes maximum 6 +
1 to 2 months 45 to 60 minutes maximum 5 to 6 +
2 to 3 months 60 to 75 minutes maximum 5 to 6
3 to 4 months 75 to 90 minutes maximum 4 to 5
4 to 6 months 1.25 to 1.75 hours maximum 3 to 4
6 to 8 months 1.75 to 2.5 hours maximum 3
8 to 10 months 2.5 to 3.5 hours maximum 2 to 3
When child drops third nap
(around 9 to 12 months)
2.5 to 4 hours maximum 2
When child drops second nap
(around 14 to 18 months)
4 to 6 hours maximum 1


Put to Bed Drowsy but Awake

As mentioned above, when a child has cycled out of their deep sleep and entered light sleep around 45 minutes, they require what they have always had to fall asleep, in order to transition to the next sleep cycle. For some children, this is just their own self-soothing techniques. For others, it is the trusted feeding, rocking, shushing or bum-patting approach. So by putting a child to bed drowsy but awake, you allow them to learn how to fall asleep without that approach, meaning that at 45 minutes, they are much less likely to need that approach again. You can aim to do this for at least one sleep per day to begin with, and slowly work up from there.


While the four month sleep regression is simply a developmental milestone and lasts anywhere from 2 to 4 weeks, unfortunately it can represent the beginning of long-term sleep issues for some children. If healthy sleep habits aren’t already in place before the regression, then the regression ‘behaviours’ will settle, but do tend to continue until healthy sleep habits are finally in place.

If you’re needing help to establish healthy sleep habits after the four month sleep regression, feel free to contact me because I would love to help you!

I’d love to hear your thoughts on the topic!