Why does my baby cry in their sleep?

It can be really upsetting to see your baby cry in their sleep, but often it’s entirely normal. So it’s useful to know how babies actually sleep, why they sometimes seem to be disturbed during their shut-eye, and what can you do to help.  

How babies sleep

As you’ve probably noticed, babies don’t sleep in the same way as children or adults. Not only do they sleep for longer overall, and in shorter bursts (particularly newborns), their sleep patterns are also different (BASIS, 2018). The main difference is that they spend more time in rapid eye movement (REM) sleep than adults (Barry, 2021).

REM sleep is when your baby is dreaming, it's also known as light sleep. You might notice their eyes moving behind their eyelids. They might also jerk or twitch, and their breathing may become irregular (Leigh, 2016). They may appear unsettled, but these sorts of movements are just part and parcel of your baby going through their natural sleep cycle. 

During light sleep, the brain works hard processing new memories, filing away information and matching it with other similar experiences (Barry, 2021). With so many new experiences to absorb, it’s no wonder babies can sometimes get overwhelmed.  

The six stages

REM sleep, or light sleep, is just one of six stages your baby goes through each and every day. You probably recognise them. The others are deep sleep, drowsy, calm alert, fussy alert and crying (Leigh, 2016).

If your baby cries out in their sleep, they might just be letting you know they’re passing from one stage to the next. Often, they will simply settle back down again, but sometimes the change makes them wake up. 

What should I do if my baby cries in their sleep?

If your baby cries during the night, before picking them up to comfort them, try leaving them for a moment or two. See if they are able to drift back into more restful sleep on their own. 

Your baby might just have a lot of brain development going on as they progress mentally. Strange as it sounds, these mental leaps can make your baby more unsettled for a while, and cause crying and sleep regression (Rijt and Plooijt, 2017).

If the cry is more urgent and they seem unable to settle, they might be too hot or too cold. Or they might need a feed or have a cold and wet nappy. 

As your baby grows you’ll be able to better pinpoint what’s happening. But as with all parts of parenting, the learning curve is steep. Whatever it is, try to keep the disturbance to a minimum, and the atmosphere peaceful and calm. This way your baby will get used to the idea that night-time is for sleeping. 

In most cases, occasional crying in their sleep is entirely normal and nothing to worry about. But if you are worried about persistent crying in longer bursts, remember you can contact your GP or health visitor. 

This page was last reviewed in November 2021

Further information

Our support line offers practical and emotional support with feeding your baby and general enquiries for parents, members and volunteers: 0300 330 0700.

You might find attending one of our NCT New Baby groups helpful as they give you the opportunity to explore different approaches to important parenting issues with a qualified group leader and other new parents in your area.

Make friends with other parents-to-be and new parents in your local area for support and friendship by seeing what NCT activities are happening nearby.

Watch our coping with crying film.

The Purple Crying website looks in detail at the stage in your baby’s life when they cry more than at any other time.

Understanding childhood also have a range of resources available online and to download, developed by child psychotherapists, including a leaflet on crying.

There’s also useful information on the NHS website.

The NSPCC helpline provides help and support to thousands of parents and families.

The Lullaby Trust has lots of useful information and support for parents about safe sleep.