Baby Cries In Sleep: What To Know And How To Soothe Them

Picture of Robyn Rosenblum, MD, FAAP

older sibling laying with new sibling

Sleeping like a baby doesn’t always mean you get a full night of rest. Unfortunately, crying in their sleep is normal for babies.

We know you’re hoping for a quiet night once bedtime rolls around, but sometimes that doesn’t happen. Hang in there, parents, because just like everything else in your baby’s life, this is a passing phase!

Let’s take a look at everything you need to know when your baby cries in their sleep.

Table Of Contents

Why Do Babies Cry In Their Sleep?

baby cries in sleep

Babies cry to communicate. They aren’t doing it to annoy you or to make you mad. They are trying to tell you something.

Unfortunately, they can’t yet use words to tell you what’s wrong. If your little one could, they’d simply say something like, “Hey, I’m feeling a little lonely and hungry, and I really could use a snuggle.”

Since they can’t make their words come out like that, they do what they can to get your attention. They cry.

Once they start crying, you get to play detective to try to figure out what’s going on. Because as you’ll see below, babies cry in their sleep for many reasons.

Over time, you’ll understand your baby better and might be able to interpret their cries a bit more easily. For example, you may discover that one particular cry means they’re hungry, while another one indicates pain.

Until you reach that point, you’ll need your investigative skills to discover what’s wrong.

To help you better understand what could be causing the trouble, let’s look at the science behind the tears and examine some common reasons for crying at night.

Baby Cries In Sleep: The Science Behind It

twins sleeping in crib

Babies cry in their sleep for many different reasons, but it’s important to start with understanding your baby’s sleep patterns and schedule before you can determine the reason.

Newborns, for example, sleep 16 to 20 hours per day, and they wake up every three to four hours to eat, even at night, until they’ve reached their birth weight.

In addition, nursing babies digest breast milk differently than formula-fed babies, so they may wake up and eat more during the late night (or early morning!) hours. But by three months, your baby can sleep about eight to nine hours at night with a few naps during the day.

However, just because babies can do something doesn’t mean they will. Some youngsters don’t start sleeping through the night until their first birthday or even beyond. So you may have to deal with middle-of-the-night cries for longer than you’re expecting.

This process is a marathon, not a sprint. You may have a few good nights, followed by some that are terrible.

Be patient, and remember their long nighttime stretch may have a few interruptions that cause them to cry. If this happens, you may wonder if it has something to do with their crib. The first order of business is to check the quality of their crib mattress.

Our Crib Mattress is known to give babies a safer, more comfortable sleep. If you’re already using a Newton Baby Crib Mattress, check out some other possible reasons for your baby’s nighttime tears.

Switching Sleep Stages

Babies switch from rapid eye movement (REM) sleep to non-rapid eye movement (NREM) sleep. The REM stage is known as “active sleep,” and NREM is known as “quiet sleep.”

Your newborn will spend 50% of their nighttime sleep in the REM stage and the other 50% in the NREM stage. It’s during the REM stage that you might hear your baby cry in the middle of the night or move around and whimper.

That being said, the reason your baby cries in their sleep might be because they’re switching sleep stages. Fortunately, these stages change as they grow.

For example, as your baby gets older, they won’t spend the same amount of time in each sleep phase as they did when they were a newborn. Instead of spending 50% in the REM stage (which is when you would hear your baby crying and whimpering), they might spend 30%.

This means that, as your baby grows, they won’t cry as much in their sleep since their sleep patterns and phases are changing. There’s light at the end of the tunnel! You will get some nighttime sleep...eventually.

Uncomfortable, Sick, Or Hungry

There’s always the chance that your baby is uncomfortable (diaper change, anyone?), not feeling well, or hungry.

Newborns especially tend to wake up a lot in the middle of the night because they’re hungry (or just need to be held).

Here are some other possible causes of discomfort that could cause crying:

  • A thread from their pajamas wrapped around a toe
  • They rolled into an uncomfortable position and got stuck
  • They’re cutting a tooth
  • It’s too hot or too cold in their room
  • They pulled their foot up into their pajamas and can’t get it back in place
  • Their arm was in a weird position, and it fell asleep and is now tingly
  • A gas bubble is stuck and causing pain
  • They’re going through a growth spurt
  • Their diaper isn’t on right, or the tab is stuck to their skin
  • There’s a tag on their clothes that’s bothering them
  • Their clothes don’t feel good on their body
  • They stayed up too long and are now overtired

As you can see, lots of little things could be going on. If you think your baby is uncomfortable, do a quick investigation for any obvious signs. Sometimes a change of clothes, a fresh diaper, and a quick feeding can help make your little one happier.

But sometimes, they keep crying even after you’ve tried all that. In that case, it’s time to put your detective hat on and try to figure out what’s wrong. To help you get back to sleep, let’s look at a few more common reasons babies cry in their sleep.

Separation Anxiety

Dad picked up baby after baby cries in sleep

Sometimes your baby just misses you and cries out for you to come be with them. Or they thought about you while they were sleeping and started crying because they wanted you to hold them.

This doesn’t happen too much in younger babies, but it’s pretty common in babies around nine months old. By this age, most little ones are figuring out object permanence. They know that you’re around even when they can’t see you.

And since you’re there somewhere, they want you to be with them. To tell you that they want you, they cry.

This separation anxiety is common and often worse when your little one is tired or not feeling well. It could also be labeled as a type of “nightmare” for infants, being away from their parents. After all, you are their safe zone.

Sleep Regression

When your baby masters a new milestone, like sitting up or crawling, they might experience sleep regression (a disruption in their sleep cycle). This is because their brain activity increases during this time.

Sleep regression happens around four months, six months, eight months, 10 months, and 12 months — and that’s just during their first year.

Due to this disruption and increased brain activity, their REM and NREM sleep changes, which might make your baby cry in their sleep.

Sleep Training

When your baby enters the world, they don’t know the difference between night and day. They don’t know when they’re supposed to sleep.

As strange as it sounds, this is something you get to teach them about. Unfortunately, that process can involve a few tears.

If you’re trying to use a sleep training strategy like the cry-it-out method, tears are even more common. While your little one adapts to self-soothing, they’ll cry at first. But soon, they’ll discover other ways to get back to sleep.

Depending on the technique you’re using, your response to these cries varies from ignoring them to offering reassurance. Either way, know that it won’t take long for your baby to adjust.

Regardless of what you’re thinking right now, sleep training doesn’t last forever. It’s typically over in about two weeks.

Baby Cries In Sleep: Nightmare Or Night Terrors?

baby sleeping with a pacifier

Many parents wonder if their baby could be experiencing nightmares or night terrors that cause them to cry in their sleep.

It’s really unclear when nightmares start, but they usually occur between the ages of two and four. Night terrors, on the other hand, could start happening in babies as early as 18 months.

However, there are always exceptions to the rule. If you think your baby crying in their sleep is due to nightmares or night terrors, reach out to their doctor to get more information on this topic.

How To Soothe Your Baby When They Cry In Their Sleep

Mom soothing her newborn after baby cries in sleep

Don’t Immediately Rush In

When your baby cries in their sleep, don’t rush right in. Instead, give them a few beats (if it even takes that long) to attempt to self-soothe.

However, sometimes it can be hard to tell if your little one is actually awake or asleep when they’re changing from one sleep stage to the other, so always pay attention to their cry.

Again, as your baby grows, you’ll begin to recognize their hungry and sick cries and learn to tell them apart from their uncomfortable or transitioning cries. This is helpful because once you know why they’re crying, you know what to do first.

Remember, babies who are wet, uncomfortable, hungry, or sick will continue crying. Use your best judgment and check your baby’s temperature and crib.

It also helps to spend some time watching your little one sleep when they’re not crying. You can see what they do as they move from one sleep stage to another. These observations
help you identify what’s normal for your baby.

For example, some babies fuss for a few minutes before they fall asleep. Others might let out a cry when they move into a deep sleep. Or they might whimper right before they wake up.

Once you know what is typical for your baby, you’ll have a baseline to go by. If you hear sounds that aren’t normal, it’s time for further investigation.

Check Their Position

Before picking your baby up, take a peek at how they’re lying in their crib. Are they in the middle of the mattress on their back? Or have they managed to roll and wedge themselves into an uncomfortable position?

If they’ve rolled or turned, sometimes carefully moving them is enough to help them stop crying and get back to sleep. Just remember to keep the safe sleep guidelines in mind and put your little one on their back until they turn one.

Cuddle With Your Baby

Sometimes your baby just needs middle-of-the-night snuggle time with mom or dad, especially if they’re having separation anxiety because of a change in their daytime schedule (like mom or dad going back to work).

Pick them up and hold them close for a while. Offer reassuring words or sing a quiet song. You can also rub their back or belly to help soothe them.

Once your little one is ready to go back to their crib, take it slowly. Let them know you’re still there and that you love them very much. Continue rubbing their belly for a few minutes after getting them into their crib to help them stay calm through the transfer process.

Adjust Their Swaddle

Your little one might squirm out of their swaddle and become uncomfortable while they’re sleeping. Simply adjust their swaddle blanket so they’re tight and cozy in it.

(Expert tip: it’s not safe for your baby to have a regular blanket, so use a swaddle blanket to keep them comfortable and at the perfect temperature, so they won’t start crying in their sleep from a sweaty back.)

It’s also important to remember to only swaddle babies younger than four months old. At this age, babies tend to start rolling over, which makes swaddling them an unsafe sleep practice.

Ways To Help Your Baby Sleep Better

baby sleeping in a crib

Now that you know why your baby might be crying in their sleep and what you can do to help them settle back down again, here are some general tips for better slumber.

Develop A Bedtime Routine

One of the ways you can help your baby get used to the concept of sleeping at night is through a consistent bedtime routine. Before putting them into bed for the night, make it a point to do the same things each evening.

A consistent bedtime routine calms your little one’s body and mind and teaches them that it’s almost time for sleeping. Your routine doesn’t need to be long or complicated.

Keep it simple by selecting a few of these activities and doing them in the same order night after night:

  • A warm bath
  • A quick massage with baby lotion
  • Cozy pajamas and a sleep sack (or swaddle blanket)
  • Singing a song
  • Reading a bedtime story
  • Placing them in their crib with a kiss
  • Turning down the lights and saying, “Nighty night.”

Use A Sleep Sack

One way you can help your baby sleep better is by using a sleep sack, which is the next step after swaddling.

Sleep sacks keep your baby nestled in but give them more room to move their arms. This is important for when they start rolling over because their arms are free, allowing your little one to push themselves back over.

You can keep using a sleep sack until your baby is about one year old. At that point, they can safely use a regular blanket.

Keep Their Room Dark

Dark nursery to prevent baby crying in sleep

Some babies cry in their sleep because their environment is not to their liking. Specifically, any type of light may startle them while they’re sleeping, causing them to cry.

Set the mood for the night for your little one by closing the door all the way and using a nightlight that gives just the right amount of light so your baby can see their surroundings if they do wake up.

If you do need to go in and check on them, keep the lights low. This way, you’re helping them learn that darkness and sleep go together.

Use A White Noise Machine

Bedtime is often when you are able to get things done around the house, but that’s not always feasible if your baby continually wakes up crying.

Maybe there are older siblings in the house who just make a lot of noise because, well, they’re kids and that’s what kids do. Or possibly your home gets a lot of street noise.

Whatever the case may be, using a sound machine can help block out these noises in the house. Plus, the soothing sounds can help lull your little one back to sleep if their crying wakes them up in the middle of the night.

Note: Some studies have shown that white noise machines can cause hearing damage when used incorrectly. While more research is needed, it’s best to place the machine several feet away from your baby’s crib. You should also keep the volume below 50 decibels.

When To Call The Doctor

If your little one cries in their sleep every now and then, it’s really no cause for concern. However, you know your child best and what’s normal and what’s not.

If your baby has excessive crying at night that disrupts their daytime routine, it could be caused by:

  • Colic
  • Acid reflux
  • Milk allergy
  • An upset tummy (for example, something you ate is bothering their tummy if you’re nursing)
  • Sleep apnea

If you suspect any of the causes above or have concerns, don’t hesitate to reach out to your child’s doctor.

Sleeping Soundly

baby sleeping on side in crib

We know how important it is for your baby to have healthy sleep patterns and a safe sleeping environment. We also know it can be hard to wake up to your little one crying in their sleep.

Most of the time, there’s no need to rush in to save the day. More than likely, your baby is just changing sleep stages, and it causes more disruption to your sleep than it does to theirs.

However, there are ways you can soothe your little one if they don’t stop crying, and it’s always important to pay attention to their cry. Use your best judgment, and if their cry seems to linger, check their temperature and crib.

Keeping their room dark and using a white noise machine are a couple of great ways to help your baby sleep well. And, of course, sleeping on a Newton Baby Crib Mattress gives your baby the best chance of snoozing safely and soundly!

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