The 4 month sleep regression: What is it and how can you get through it?

4 month sleep regression baby sleep advice baby sleep team regression sleep advice

I knew very little about sleep before I had babies. Why would you? You never think twice about it. That is, until you don’t get enough of it. Then you can become strangely fanatical about it. Or is that just me?! 

The four-month sleep regression was something that was talked about in my mother’s group well and truly before our babies even reached that stage. I was worried about it and didn’t understand it and we had no idea how each of our babies were going to react and come out the other side. How much would their sleep be broken? Would they ever sleep normally again?

So what is it?

In a nutshell, the four-month sleep regression is a developmental leap that occurs anywhere between 3-5 months. During this change, your baby moves from newborn sleep stages to having sleep cycles that are aligned to adult sleep cycles. Just when you thought you were getting into a bit more of a rhythm and predictability with your newborn, they then can start waking a lot more and become fussier.

Is it really a regression?

Not really! It’s a fundamental shift in terms of the sleep patterns of your baby. It is not a temporary change, it is a huge developmental change in your baby’s brain that is a permanent change. Your baby is growing up and they will have these sleep cycles forever.

Will the sleep regression impact my baby’s ability to sleep through the night?

Sleeping through the night is actually a myth! It’s important to understand that night wakings are a regular feature of normal, healthy sleep. Both adults and babies will wake up multiple times a night as we move from one sleep cycle for the next. The difference is that adults know how to fall back to sleep whereas this is a skill that babies need to learn.

Tell me the science behind it? 

It can be easily explained in a simple table:

  Adults Newborns
Time Spent in REM 25% 50%
Time Spent in Non-REM 75% 50%
Number of Cycles/Night 4-6 More than adults!
Duration of Cycle 90 minutes 30-50 minutes

Definitions (Defined by the National Sleep Foundation)

REM: Rapid eye movement. Light but active sleep when dreaming occurs.

Non-REM: Non-rapid eye-movement.This is broken down into 3 stages:

  • N1: The light sleep which is between being awake and falling asleep.
  • N2: Light sleep when your breathing and heartbeat are regular, your body temperature drops slightly and you become unaware of your surroundings.
  • N3: This stage is when the deepest, most restorative sleep occurs. Breathing slows, muscles relax, tissue growth occurs and energy is restored.
Sleep Stages of Your Baby

There are also other things going on for your baby at the same time!

In addition to your baby’s brain-changing to the same sleep cycle as an adult, during this time there are also a lot of other changes happening:

  • They are becoming more active
  • Your baby is learning to roll
  • They are starting to recognize faces
  • Usually between 3-4 months, your baby goes through a big growth spurt which can result in extra feedings to increase calories.
  • Your baby is a lot more aware of their surroundings and what is happening in their world. This means that during feedings they can become distracted and not intake full feedings.

What does this all mean for my baby?

Every time your baby reaches the end of a sleep cycle moving into a lighter state of sleep, they now have the opportunity for a complete wake-up. Even though as adults, we go through the same cycles, we most likely don’t even remember these wake-ups. For your baby, however, if they have been reliant on a sleep association, or a sleep prop to get them to sleep, if that association is not there when they wake, they are unable to get back to sleep on their own.

Let’s relate that to us. What if we went to bed and we fell asleep blissfully all snuggly and warm in our own bed. The next thing we know is when we wake up next, we’re lying on the kitchen table! Of course, you would wake up with a startle and wonder how on earth you got there! It’s no different for our babies.

What can happen next?

So often, when our babies wake during the night, what do we do? We feed them! Especially if they are going through a growth spurt we assume that they are always hungry. But THEN what happens is that after they have been fed and put back down to bed, they can wake up anywhere between 1-2 hours later. So we feed them again! You can see how quickly you then can get into a repeat pattern of your baby continues to wake up because they can’t fall asleep on their own, but now they have become reliant on a feed to go back to sleep. And so the sleep deprivation begins.

It can be such a challenge for parents to not know if their baby is genuinely waking up hungry, or if it has now become a habit wake. This can continue for a long time and as a result, the whole family can suffer from utter exhaustion.

So, what can I do about it?

  1. Slowly break sleep associations
  2. Work on reducing the amount of input you are having to put your baby to sleep.
  3. Practice putting your baby down drowsy, but still awake.
  4. The best opportunities to practice this are for the first nap of the day and going to bed at night.

Create a perfect sleep environment

  • Use a white noise machine so that you create a 1) consistent sleep environment and 2) musk household noises to minimize wakes
  • Make sure that the room is the appropriate temperature. This should be between 65°F and 72°F (18°C to 21°C)
  • Appropriate clothing will ensure that your baby is comfortable to sleep. This includes using a Swaddle blanket or a baby sleeping bag.
  • Blackout curtains will block out any light creeping into the room which will help your baby also sleep. Don’t worry…they are not afraid of the dark! They have been in the womb for 9 months and love dark places!
  • Introduce a cuddly. A cuddly can prove to be an immensely effective tool to help your baby self-settle.

Feed as much as needed

  • Make sure that you are maintaining regular feeds so that your baby intakes their required calories during the day.
  • If you find your baby is being distracted by their new, exciting world, take them into a non-stimulating environment (without phones, with dim lights, etc) to ensure they take in full feeds.
  • Offer more feedings to meet your baby’s required calorie intake if they are going through a growth spurt.
  • Make sure that when you baby is feeding, they are not falling asleep. This maintains the volume they are taking in.

Consider a dream feed

Your baby is still young and it is very common for babies at this age to need to feed at least once at night. The best time to introduce a dream feed is somewhere between 9.30 pm-11 pm at night.

Create a predictable bedtime routine

Babies thrive on routine. It doesn’t have to be a long elaborate, drawn-out process. You can simply have in place a routine that lasts between 20-30 minutes. Do 3-4 steps in the same order every single night! It helps cue to your baby that sleep is approaching and it prepares them for bed.

Adjust the baby’s bedtime

So many babies are going to bed far too late which puts them in a sleep-deprived state. A common myth from many parents is that if you put your baby to bed too late, they will sleep longer. The opposite is actually true! Not getting enough sleep will make a baby overtired, their cortisol levels will increase making it even harder to fall asleep and it will lead them to be fussier during this stage.

Give them time to practice during the day

Your baby is learning to roll and move around and explore their new world. Make sure you give them plenty of time during the day to practice these new skills. Tummy time and lots of time on the floor will help them master these new skills.

Pause before you rush to your baby during night wakes

As adults, when we wake up in between sleep cycles, we might change our sleep position, fluff our pillow and make ourselves comfortable again. It’s completely natural that when our babies wake, we feel like we need to leap out of bed and comfort them straight away. Try to give your baby a few minutes to see if they will re-settle first before you pick them up. If they are in the process of settling on their own, you may be depriving them the chance to go back down by intervening too soon.

Have a support partner

Any major sleep regression can be a challenge and exhausting for the parents. Make sure that you’ve got support around you and if you can, alternate with your partner when you’re needing to settle your baby.

If nothing is working?

We’re available for 1:1 consultations to work through your little one's sleep challenges and create a plan that works for your family.