The four-month sleep regression

Somewhere between about 3 and 6 months, some babies start to wake up more during the night.

Welcome to the “four-month sleep regression!”

The regression happens after a period when your baby might have started sleeping for longer stretches during the night.

Suddenly they start to wake more frequently and sometimes to feed more frequently too

Sleep advantages that are happening now

• They are establishing mature sleep cycles and experiencing deeper sleep
• They are making their own sleep hormones
• They are bigger and need less milk at night

Sleep cycles

Around this time, babies settle into a mature pattern of sleep cycles – with light sleep, deep sleep and waking phases. Each sleep cycle lasts about an hour.

This means that they wake up during the night as they go through these sleep cycles.

Sleep hormones

Your baby is now producing their own sleep hormones, such as melatonin. Previously for night time sleep, they relied upon being close to their parent – sharing their circadian rhythm.

Getting bigger

Young babies need to feed regularly, including during the night. They are growing very rapidly and their little tummies can’t hold enough milk to sustain them for long.

At around this age, their rapid growth settles into a slower and steadier weight gain. Many babies of 4 months have the body weight to enable them to sleep for stretches of 5 hours or more at night without getting hungry. 

So given that all this positive stuff is going on, it can be frustrating when babies start to go backwards with their sleeping!

Why does this happen? 

It is because also between 3 and 6 months, babies become more conscious of what is going on.

They start to figure things out and make learning connections. 

These connections, made as they fall asleep, can develop into expectations and preferences around their night sleeping and napping. In other words – habits are formed.

So as an example – if they are fed or cuddled to sleep at the start of the night, they may need or expect those same “sleep triggers” when they wake up naturally after a sleep cycle.

Of course, it is fine to cuddle or feed your baby to sleep if that’s what feels right for you or if that’s what they need. Be aware though that if at this age, they start to wake for feeds and cuddles more than they used to; there is a good chance that they are doing out it of habit rather than need.

This can be disruptive to their sleep and yours also. 

How to deal with it

A good bedtime routine really comes into its own now. You need a repeated series of steps leading up to bedtime that baby will recognise as sleep cues. 

Then unless you’ve chosen to co-sleep, it’s good to help them fall asleep in the cot aware of where they are. A lovely way of doing this is to give the last feed with the light on and follow it with a simple book. Then lights off and put them down into the cot awake. Soothe them there if they don’t like to be left, or leave them to self-settle if they’re ok with that. 

As sleep now happens in cycles; it is normal to wake a few times in their sleep. When your baby wakes up, they will need to have everything around them, the same as it was when they fell asleep. 

So the more independently they fall asleep at the start of sleep, the more likely they are to be able to join their sleep cycles by themselves. 

If they do wake up, try soothing them in the cot for a while rather than automatically picking them up or feeding them. They might just resettle and drift back off, but of course, if they continue to cry, it is best to respond with whatever feeding or cuddling they need. 

Watch out that they don’t feed so much at night that they have no appetite for feeds during the day. This is such a common situation and is called reverse cycling. If your baby feeds a lot during the night you might find that they feed distractedly during the day. You may be constantly trying to tempt them or persuade them to feed during the day! As soon as it is dark and quiet, they will take good sustained feeds. Soon it becomes an established feeding pattern; one that can be difficult to break away from. How can you possibly stop the night feeds if these are the only ones your baby takes?

If you WAIT for your baby’s daytime appetite to improve before reducing night feeds, you’ll be waiting forever! The way to approach this is to cut down on the night feeds and then you’ll find that the daytime feeds will gradually increase.

Will this regression pass by itself?

For some babies, this is a phase and it will pass. For others, the habits which form during the period of regression can stick, meaning that their wakeful nights become the norm. If you’re struggling, you’ll find more help to establish good sleep habits in my Gentle Sleep Course and also in my book, Gentle Sleep Solutions.

Does every baby go through the four-month sleep regression?

No! Many babies naturally sleep for longer periods as they get bigger and older. This is especially true of babies who have a naturally very calm disposition and find it easy to settle to sleep without much help.

In my experience, babies who do go through this regression are usually very alert, engaged and quick on the uptake!

Further Help

If you’re struggling with the four-month or any other sleep regression, I am here to help you.

My books

My bestselling books give you the tools to help your baby and yourself get a good night’s sleep. They are full of expert, practical advice and case studies. Each book teaches you to create your baby or child’s personal sleep plan and is written in a clear and accessible style.

They are available in all formats from Amazon and other booksellers.

My Courses

My courses are a mix of video, graphics and easy-to-read text. They are a great way to access my expert help – from your phone, tablet or laptop. The courses have no expiry date and are updated frequently. The Gentle Sleep Course is very comprehensive, easy to dip in and out of and is very empowering.

The Early Waking Course is concise and accessible – it takes around an hour to complete and it may be the best hour you’ve ever spent!

Both of the courses contain helpful schedules for day and night time sleep.

My 1:1 Consultations

If you choose to book a one-to-one consultation with me, you will receive my expert advice along with an individual sleep plan for your child. You will be in very safe, experienced hands and I treat every parent and child with kindness. As a qualified health professional, I can help families with medical and developmental issues. My success rate is outstanding, with over 15,000 face-to-face sleep consultations with families from all over the world.

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