4-Month Sleep Regression: From Sleepless to Sound

Is your once-sleepy baby suddenly wide awake at night? If your 4-month-old was settling well but is now waking frequently during the night and struggling to fall back asleep, it might be what some call a 4-month sleep regression. Keep reading to uncover what a 4-month sleep regression is, its causes and signs, and practical tips to navigate this phase.

If you're navigating a 4-month sleep regression and need support, start your free sleep consultation with the Smart Sleep Coach by Pampers™ to get a tailored sleep plan for your little one.

What Is 4-Month Sleep Regression?

You may have thought that sleep deprivation was behind you but now your 4-month-old has started waking multiple times during the night! If you’re wondering ‘Why is my 4-month-old not sleeping?’ and your GP has ruled out any medical concerns, your little one might be experiencing what is often called 4-month sleep regression.

Sleep regression is when your baby, who previously slept well, suddenly begins to struggle with sleep. They may find it difficult to settle at bedtime or cry for your attention when they wake during the night, unable to fall back to sleep on their own.

This sleep disruption often happens during a period of rapid growth or development in your baby. Around 4 months of age, their brain and body are going through significant changes – which is why a 4-month sleep regression is so common. However, every baby is unique, so while many experience this phase, others may not go through a 4-month sleep regression at all. Both are completely normal and part of your baby’s individual development journey.

One major change at this stage is the development of your little one’s sleep and wake cycle. As a newborn, your baby would have slept in shorter bursts but by around 4 months, their sleep patterns start to mature and become more like an adult’s. This may mean longer periods of sleep at night, but your little one may need time to adjust – and this adjustment phase is when a 4-month sleep regression often occurs.

What Causes 4-Month Sleep Regression?

Sleep regression can happen at any age, but it’s particularly common at 4 months when your baby’s sleep cycle is maturing. As your little one learns the difference between night and day, their sleep-wake cycle becomes more regulated. This means they’ll likely start sleeping for longer periods at night and taking fewer naps during the day.

So, why does a 4-month sleep regression occur, what factors contribute to sleep issues, and why might your baby be restless at night?

Let’s explore some common causes.

• Developmental changes. At around 4 months, your baby’s sleep cycle matures, leading to adjustments in sleep patterns and potential disruptions known as a 4-month sleep regression. Think of it as part of their growth, not a setback. Developmental milestones like rolling over, crawling attempts, teething, or growth spurts can also strain their energy, contributing to sleep challenges.

• Not able to self-soothe yet. All babies – and even adults – wake up briefly during the night. For young babies, the ability to soothe themselves and fall back to sleep independently is a skill that takes time to develop. Teaching your little one to self-soothe could possibly be key to managing 4-month sleep regression signs. 

• Lack of routine. Consistency is key. Establishing a predictable evening routine helps your baby associate activities like bath time or a lullaby with winding down for bed. By around 4 months, a clear routine can support their developing sleep patterns and ease bedtime transitions. If they’re used to being rocked or fed to sleep, placing them in their cot sleepy but awake can encourage better sleep habits. Lullabies for babies can also create a calming atmosphere.

Increased Alertness and Activity

As your baby becomes more independent and aware of their surroundings, they may find it harder to settle down at the end of the day. This heightened activity and curiosity, typical at 4 months, may lead to your little onefighting sleep. Making sure your baby stays active during the day and experiences calming activities before bedtime may help manage this alertness.

Medical Causes

Sometimes, disrupted sleep may stem from medical or health issues such as teething, colds, ear infections or constipation. If your baby isn’t sleeping well, keep an eye out for symptoms like fever, irritability or discomfort. Consult your GP for guidance on treating any underlying issues.

4-Month Sleep Regression Signs

The following changes in sleep habits might indicate that your 4-month-old is experiencing 4-month sleep regression:

• Taking a long time to settle at night

• Waking frequently during the night

• Increased restlessness or fussiness

• Disrupted daytime naps.

If you’ve noticed some of these signs in your little one, they may be going through a 4-month sleep regression. However, it’s worth keeping in mind that your baby might wake frequently or struggle to sleep for other reasons, such as teething or illness.

If you’re concerned about your baby’s sleep or suspect there may be an underlying issue, consult your GP for advice.

How Long Does 4-Month Sleep Regression Last?

Even one sleepless night could feel overwhelming and a week or two of disrupted sleep may make a full night’s rest seem like a distant dream. But you’re not alone – most parents have faced sleepless nights with their little ones.

The good news is that 4-month sleep regression typically lasts for a week or two. During this time, your baby is adjusting to their new sleep cycle and will likely start sleeping for longer stretches at night. By 8 to 9 months old, many babies begin sleeping through the night. That said, every child is unique- some may settle into a consistent sleep pattern sooner, while others may not experience 4-month sleep regression at all.

Studies have shown that teaching and forming good sleep habits while your baby is young is easier compared to when they’re reaching toddlerhood. It just takes a little (or a lot) of time and patience – but better sleep is on the horizon!

Mandy Treeby, Paediatric Sleep Coach and Co-founder of the Smart Sleep Coach by Pampers™, explains: "The act of falling asleep is a learned skill, and your baby needs the space and time to practice. Four months is the perfect time to start sleep coaching. By delivering consistent bedtime routines that always end with your baby sleepy but awake, you’re setting your baby up for sleep success from an early age!"

Can You Prevent 4-Month Sleep Regression?

As mentioned earlier, 4-month sleep regression is often linked to important developmental changes in your little one. Around four months, their sleep cycle matures, becoming more structured and similar to an adult’s. This exciting milestone may, however, temporarily disrupt your baby’s ability to sleep peacefully.

While not every baby will experience 4-month sleep regression, many parents find this phase challenging. The good news is that there are steps you may take to gently guide your little one toward better sleep habits. These strategies could possibly provide relief and help you both navigate this period with greater ease.

Read on for expert tips to help manage 4-month sleep regression and encourage restful nights for your family.

Tips: How to Deal With 4-Month Sleep Regression

There’s no ‘one-size-fits-all’ solution for 4-month sleep regression, but there are plenty of strategies you can try to support your baby’s sleep during this tricky phase. With time, patience, and these helpful tips, you and your little one may work through this stage and move towards more restful nights.

1. Encourage self-soothing. Many babies struggle to fall back to sleep on their own because they rely on their parents to soothe them. Instead of immediately rushing to your baby when they cry at night, try gradually extending the time before responding. This technique, known as the Ferber method or graduated ‘cry-it-out’, helps your baby learn to self-soothe. 

2. Create a bedtime routine. A consistent bedtime routine may help your baby relax and establish healthy sleep habits. You might include calming activities like a warm bath, gentle rocking, a soothing massage, cuddling or a bedtime lullaby. A simple story before bed could also help your little one wind down and prepare for sleep.

3. Recognising the cues. Understanding when your baby is ready for bed may make a big difference. Aim to put them down when they’re sleepy but still awake. This encourages your baby to learn how to drift off independently. Common signs of sleepiness include yawning, rubbing eyes, pulling at ears or becoming fussy. Acting on these cues may support their ability to self-settle.

4. Feed before bedtime. During 4-month sleep regression, your baby is experiencing significant growth and development, which may increase their hunger levels. Ensuring they’re well-fed throughout the day and offering a feed right before bedtime may help minimise night-time wake-ups due to hunger. For more insights, check out this guide on when babies start sleeping through the night.

5. Keep nights calm and days active. Create a calming bedtime environment by dimming the lights, speaking in soothing tones, and avoiding stimulating activities, toys or screentime in the evening. During the day, focus on keeping your baby active, exposing them to natural light, and engaging in playful interactions. This contrast between calm evenings and active days helps regulate their sleep-wake cycle and encourages a better night’s sleep.

When to Consult Your Baby’s Doctor

It’s possible that sleep disruptions or 4-month sleep regression may be linked to sleep disorders or underlying health concerns. It’s important to consult your child’s GP if:

• Your baby is unusually irritable and difficult to soothe, which could indicate colic, a common cause of sleep disruption and fussiness. 

• You suspect their sleep issues may be caused by an ear infection, reflux, or a condition like sleep apnoea. 

• Your baby has breathing difficulties.

• You find it difficult to wake your baby from sleep.

If you notice these symptoms or have concerns about your baby’s health, don’t hesitate to reach out to your GP for guidance.

The Bottom Line

The arrival of a newborn often brings sleepless nights, but as your little one grows, they will begin sleeping longer stretches – or even through the night. Around 4 months, however, their sleep cycle starts maturing, which may temporarily disrupt their rest. This phase, known as 4-month sleep regression, is a normal part of adjusting to new sleep patterns.

To help your baby sleep better, try encouraging self-soothing, establishing a calming bedtime routine and ensuring they’re well-fed before bed. With patience and consistency, peaceful nights are on the horizon!

Don’t forget to download the Pampers Club app to earn rewards on every pack of Pampers nappies, nappy pants and wipes – because your little one deserves the best!

_{How We Wrote This Article The information in this article is based on the expert advice found in trusted medical and government sources, such as the National Health Service (NHS). You can find a full list of sources used for this article below. The content on this page should not replace professional medical advice. Always consult medical professionals for full diagnosis and treatment.}