What age do babies go into deep sleep?

Babies have different sleep patterns. Some take long day naps while others only have quick naps. Some wake up frequently through the night while others may sleep through or wake up occasionally. Their sleep patterns can also change a lot in the first year. While each baby is different, it may help you to understand how babies' sleep cycles differ from those of adults and also what to expect at each stage.

Normal baby sleep versus adult sleep

Babies under 1 are naturally lighter sleepers compared with adults. They spend more of their sleeping time in 'active sleep' instead of 'quiet sleep'.

In active sleep, babies breathe shallowly and twitch their arms and legs. Their eyes flutter under their eyelids. Babies can be easily woken up from active sleep.

By comparison, adults and adolescents tend to have more quiet sleep, where they lie still and breathe deeply.

Everybody has a cycle, where their sleep varies from light to deep. Adults' sleep cycles are usually about 90 minutes. Babies' sleep cycles are usually about 40 minutes, so they tend to wake up more often.

All babies are different

Babies are little individuals so they are all different. The information below is a general guide and your baby might be different. Try not to spend too much time comparing how your baby sleeps with other babies. For advice or support at any time, call Pregnancy, Birth and Baby on 1800 882 436.

New parents can expect to get less sleep. For a few months, most of your sleep will be in short stretches. These tips will not make your baby sleep through the night, but they may help YOU get more rest.

Between 3-6 months is probably the trickiest period of baby sleep. During these few months, your baby's sleep will become a lot more like ours as adults, with more distinct periods of light and deep sleep and more neurologically differentiated sleep cycles. It is during this time that a baby's sleep habits are really becoming important too. Let's have a look at what is happening for your wee one at this time...

  • When do baby sleep cycles begin to change?
  • How daytime sleep cycles work
  • Nighttime sleep stages
  • How much sleep does a 3-6 month old baby need?
  • Oversleeping and Catnapping
  • Starting solids and Night feeds
  • The importance of routine

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When do baby sleep cycles begin to change?

  • A baby's daytime sleep cycles are not as pronounced as they will later become
  • Babies this age do not consciously rely on a series of sleep cues or behaviours in order to fall asleep.

The biggest change in your baby’s sleep cycle happens at around 4 months old and this is commonly known as the 4 month sleep regression. It is possibly the biggest change in your baby’s sleep that will ever happen!

Here are some of the changes you can expect to see:

  • Your baby’s sleep cycles become more organised and their sleep starts to operate much like ours as adults.
  • Sleep has become a very conscious thing for your little one and it takes practise for them to get this skill right.
  • They will start to wake fully between each sleep cycle rather than drift between cycles automatically.
  • If your baby is relying on a parent-led sleep association like rocking or feeding etc, they will now need you to replicate this EVERY time they wake between cycles (Every 35-45 minutes in the day and 2 hours overnight)
  • Your baby won't go back to sleep after that cycle if they can’t self-settle, therefore they will end up being overtired in the evening. This is known as catnapping (more on this later!).

Unfortunately, this sleep regression won't go away until your baby has learnt how to self-settle. This simply means your baby is able to fall asleep on their own when they’re ready to. Self-settling doesn’t just develop overnight, it is something new for babies and they need coaching, consistency and the chance to work on this new skill.

How daytime sleep cycles work

Your baby starts to fall asleep and enters a light sleep stage. This is where they can easily be woken by wind, being put down if held, or a sudden noise.

Your baby starts to enter a deep sleep stage and will become unaware of their surroundings.

Your baby is deeply asleep. Their breathing is deep and regulated and this is the most restorative part of their sleep cycle.

Your little one starts to come out of their deep sleep stage and if they are over/undertired, they can wake fully at this point.

Stages of night time sleep

Babies sleep cycles are longer in the night than in the day and they are sleeping their deepest between bedtime and midnight. Take a look at this chart to see how a baby’s night-time sleep works:

This is where your baby rouses out of their first night-time cycle. They will now enter a very deep sleep phase that lasts until midnight. In this phase they are less likely to wake unless they are sick or hungry.

Your baby’s deep sleep phase ends and they enter a lighter sleep phase. In this phase they are more likely to be woken if they are under or over tired, hungry, cold, sick or uncomfortable.

Your baby’s sleep cycles are 2 hours long, so every 2 hours they will enter a very light sleep phase and can rouse fully at the end of the cycle. This is where some babies might need help going back to sleep if they can’t self-settle.

Your baby is at their highest chance of waking here. If they can wake, it can be very hard to get them back to sleep, especially if they’ve slept well overnight up until this point.

Sleep is as much a nutrient for babies as milk. It is just as important for their growth and development. In order to encourage good night sleep, babies need to have age-appropriate day time naps.

Babies need a delicate balance of day sleep vs night sleep. Too much OR too little day sleep will make them harder to settle and can also lead to night waking or early morning waking.

To find out more about the importance of napping for your little one check out our article here

So, how much sleep does my 3-6 month old baby need?

By 3 months of age, most babies will be sleeping around 15 hours over a 24 hour period. Between 3-6 months old, babies generally have between 3-3.5 hours of daytime sleep, spread across 3 naps, with around 12 hours overnight sleep. They will need between 2-2.5 hours of awake time between each nap and before bedtime.

Babies vary in the scale of their sleep needs and some do need slightly more sleep than others. This is why the awake times in our Little Ones App are the maximum - this way you can assess your own baby’s sleep needs and tweak the times to suit your little one.

The chart below shows the approximate number of daytime sleep hours your little one should be getting for their age.

NOTE: When creating a nap pattern for your little one, always allow for 12 hours sleep overnight.

AgeTotal Daytime Sleep (approx)NapsAwake time between naps3-4 months3.5 hoursx3Between 2hrs - 2hrs 15 mins5-6 months3 hoursx3Between 2 hrs 15-2hrs 30 mins

How many naps are appropriate per day?

By 3 months your little one should have consolidated their sleep into three naps across the day - ideally a shorter nap in the morning, longer nap at lunchtime and a short, late afternoon nap.

We believe it is vital to establish and maintain a long restorative nap of approximately 2 hours across the middle of the day when there is a natural dip in their energy levels.

Our reason for aiming for this long consistent nap is that during restorative sleep, babies enter REM and this is where a whole lot of amazing stuff happens! For example, their appetite and emotions are regulated, stress and cortisol levels are reduced, new skills and memories are consolidated, their immune system is boosted and brain connections are made and strengthened.

Now, napping is hugely important for your little ones development, but having the right amount of awake time is just as important, as too much awake time can lead to over tiredness, while too little awake time can lead to under tiredness. Both of which lead to poor napping and/or poor nighttime sleep. This can mean a grumpy baby and very frustrated parents!

Between the ages of 3-6 months your baby needs a lot more awake time than when they were a newborn. At this age, your baby is a lot more aware of the world and will love playing, laughing and visual stimulation.

So, if you're still trying to put your 3 month old to bed after an hour of being awake, you're most likely going to experience a lot of protesting from your wee one or you'll have to do a lot more rocking or feeding to get them to go to sleep in the first place!

Between 3-6 months old babies need between 2 - 2 ½ hours awake time between each nap and before bedtime in order to settle easily and sleep well.

Following the age-specific sleep and feed schedules in our Little Ones App helps to take the guesswork out of your baby's sleep needs and ensures they are getting the right balance of awake time and sleep throughout the day and night.

What if my baby needs more sleep?

The answer is yes! Too MUCH day sleep can lead to difficulties settling, a lot of night waking and early morning waking - simply because your baby needs more awake time.

Now, if your baby is having some longer naps during the day, but is still settling easily and sleeping well overnight - great! Enjoy the extra sleep while you can! If they are settling and sleeping well both day AND night, it means their balance of awake time and sleep is spot on.

BUT if your little one is becoming difficult to settle, or they have started to wake more overnight, it might be time to take a closer look at the awake time and sleep they are having during the day. And here comes the sometimes contentious part - you may need to WAKE YOUR BABY.

I know, shocking right? While it might seem counter-intuitive (or even downright mean!) to wake a sleeping baby, we do advise doing this if your baby is at risk of having had too many daytime sleep hours, or they are sleeping for too long in the morning nap, which will mean their lunch nap is consequently shorter, or if they're sleeping too late or long in the afternoon, which will have a negative impact on their bedtime settling and nighttime sleep. For more info see THIS article.

What if my baby just wants to catnap all day?

How do I deal with catnapping?

If your baby is catnapping, your best line of defence is to allow them to learn to self-settle at the start of naps. Even then, some babies will need help to resettle during a nap to get a longer stretch of sleep - this is completely normal and for some babies it can last quite a while! Resettling them here rather than getting them up from their nap helps teach them to sleep for longer.

It is in this tricky sleep stage that it is important to foster good sleep habits, so aiming to have your baby do at least one nap a day in their bed is a great way to head towards better sleep.

To read more about catnapping and what causes it, read our catnapping article here.

Starting solids and the effect on sleep

Between the age of 4-6 months your baby may start showing signs of being ready for solids. If this is the case, you should consult with your healthcare practitioner about the best way forward. Many babies do start on solids in this age bracket and one of the signs of readiness (along with other signs) is more frequent night waking out of genuine hunger.

There is a long-standing myth that starting solids will quickly mean your baby is sleeping better at night, however, this is not necessarily true. When your baby starts solids, the amount they will be taking is relatively small, increasing every few days, so the impact on their night sleep won't be very noticeable right away.

We advise caution around the timing of solids too - lunch is the best meal to start with and babies under 10 months should be careful about having lots of protein close to bedtime as it can sometimes cause MORE night waking due to a baby's inability to effectively digest protein at night when their metabolism is slowed.

For more information on when and what solid foods to offer your baby, our Little Ones App has everything you need to ensure you get off to a good start!

Night feeds - when can you stop them?

We can't tell you when to stop night feeds as it depends a lot on the age of your baby and their calorie intake during the day. We can tell you that it’s very normal for your baby to still be having 1-2 feeds at night until they’re well established on solids. And between 4-6 months, as babies gear up to start solids, it's quite common for them to wake for an additional feed.

It’s not always going to be hunger waking your baby overnight, so we suggest ruling out some other factors first before tackling any night weaning:

  • Too much or too little day sleep

The first thing you'll want to rule out is if your baby’s night waking is being caused by them having had too much or too little day sleep or if their naps aren’t quite at the right times during the day to promote good sleep overnight. The age-specific sleep and feed schedules in our Little Ones App can help with this.

It's also worth looking at your baby's sleep environment. We recommend sleeping your baby in a dark room to promote the release of the sleep hormone, melatonin and you can also try using white noise to help your baby sleep more deeply and link their cycles together. A swaddle (for babies who aren't rolling yet) or baby sleeping bag will also help to regulate your baby's temperature overnight.

Ideally you want to make sure that your little one is getting enough calories in their waking hours to sustain them overnight, so that they are less likely to wake hungry.

Once you’ve ruled out all of these factors, you can look at when your baby is waking for a feed in the night. If they are waking and feeding 2 hourly and they are over 4 months old, this is usually a settling issue, rather than genuine hunger - especially if they can go for longer than 2 hours between feeds in the day.

NOTE: Hunger can be an issue with babies between 4-6 months. A hungry baby will not settle or sleep. However, whether you are breast or bottle feeding, there are factors that need to be considered if you feel your baby seems to be constantly hungry or unsettled, such as an undiagnosed tongue tie, reflux or low milk supply. If everything else seems to line up for your baby to get them sleeping well yet you suspect hunger is still the issue, talk to your paediatrician about these possibilities.

The importance of routine

Routine is a tricky word because it can imply a very rigid regimental pattern to your day and certainly for very young babies, we know that's not always entirely possible and it's not something we would even really advise.

But, in saying that, an element of structure is quite important for a baby or toddler of any age and definitely during this tricky 3-6 month age bracket.

If you think about it like this, we all have routines we follow every day. You yourself might have a morning ritual of getting up, making a coffee, having some toast and reading the newspaper before jumping in the shower. We find these situations comforting and relaxing because of their familiarity.

Babies are no different. This is why so many babies thrive on having a good reliable pattern to their entire day - feeding and napping at predictable times.

Having a short wind-down period before each nap will help your baby to fall asleep nice and relaxed. You could try:

  • Reading a story
  • Singing a lullaby
  • Reading the SAME story or singing the SAME lullaby each time is even better!
  • Nappy/diaper change
  • Cuddle and putting your baby into their swaddle or sleeping bag and saying a sleep phrase like “it’s sleepy time now”

Bedtime Sleep Routine (evening)

For bedtime in the evening, you'd want to have a slightly longer routine to really help your baby wind down from their day. Often babies can have a build up of overtiredness as the day progresses, so their bedtime routine shouldn't be too stimulating or overly drawn-out.

To find out more about creating a good bedtime routine for your baby, read this article here.

We know that this is a super tricky period of sleep for your little one as there is so much going on. Their sleep needs have changed quite dramatically, but there is no need to panic as we can ensure smooth sailing through this time with our Little Ones App.

“When my baby was 3 months old, I was lost in terms of a sleep schedule. Being a new mom was overwhelming. At around 12 weeks I slowly started losing my sanity due to sleep deprivation. My baby would only fall asleep on me. Then I found Little Ones and they have saved my life! I began implementing the structured routine, and my baby began to thrive completely. I, too, became more confident and assured about my abilities. For someone that craves structure, Little Ones provides that for me. Not only is the program gentle, the community that comes along with it has been by far the most supportive community I’ve ever been a part of. So many amazing mothers and administrators contribute daily, and it makes you feel as if you’re not alone. Thanks, Little Ones! I am forever in your debt!”- Tracy