The early weeks with a newborn can feel like an endless loop of feeding, burping, changing, and bouncing. You might feel like you’re second-guessing every decision, wondering if your baby is sleeping too much, too little, or just differently than what you expected.

Newborn sleep can be unpredictable at times, but that doesn’t mean it has to feel hard. There are things you can do to support your baby’s sleep from the very beginning. And the more you understand what’s normal (and what actually helps), the easier it becomes to make decisions with confidence.

This blog walks you through the first 12 weeks of newborn sleep — what to expect, what to try, and what to avoid — so you can feel more calm and in control, even during the fog of the fourth trimester.

Understanding Newborn Sleep Basics

Day and Night Confusion 

In the early weeks, your baby’s sleep might feel completely upside down. That’s because newborns aren’t born with an entrained circadian rhythm (or body clock) meaning they don’t yet know the difference between day and night. This is why you might find your baby snoozing peacefully during the day and waking up party-ready at 2am.

In short, the best way to help your baby learn the difference between night and day is::

• Keep daytime bright and social. Open the blinds, go for walks outside, and make daytime interactive.

• Keep nights quiet and dark. Use only a dim light for night feeds and try not to stimulate your baby too much.

These little environmental cues send a strong message to your baby’s body: daytime is for activity, and night-time is for sleep. Over time, their internal rhythm starts to fall into place.

👉 Read more on how to fix day and night confusion

Maternal Melatonin and When to Start a (Loose) Routine

In those very early weeks, your baby still benefits from your melatonin - the sleep hormone that crosses the placenta before birth. This helps explain why so many newborns are extra sleepy for the first few weeks. But by 3 to 6 weeks of age, your baby begins to rely more on their own melatonin production (which isn’t in full effect yet), and you’ll likely notice a change. They start to become more alert between feeding times, and can be sometimes hard to settle to sleep.

This is the perfect time to begin shaping a gentle rhythm to your day. We don’t mean a strict routine - just a predictable pattern of feeds, play, and sleep that aligns with age-appropriate wake windows. The right amount of awake time helps build just enough sleep pressure, making it easier for your baby to fall asleep and stay asleep.

REM Sleep vs Deep Sleep in Newborns

Have you ever watched your baby sleep and thought they looked... not very asleep? That’s likely because they’re in REM sleep - a lighter, more active phase where they might grunt, twitch, wriggle or even cry out briefly. Newborns actually spend 50% of their total sleep time in REM sleep, so lots of movement and noise is a completely normal part of their sleep. 

It’s easy to assume they’ve woken up, but more often than not, they’re simply cycling through sleep stages. Picking them up too quickly can actually interrupt their natural sleep patterns. If their eyes are still closed, wait and observe. Many babies will resettle and drift into deeper sleep without any help at all.

Understanding this can take so much pressure off. You don’t have to jump in at every sound. Sometimes, doing nothing is the best support you can offer.

Witching Hour Fussiness and Bedtime Challenges

The dreaded witching hours - when your baby seems to unravel just as you’re hoping to wind down for the day. This fussy period often starts around 3 weeks and peaks near 6 weeks of age. It can feel relentless, but it is developmental and it will pass.

During this time, your baby may cluster feed, cry more often, or resist sleep altogether in the late afternoon and evening. What helps? A solid daytime rhythm, full feeds, and avoiding overtiredness. While it's exhausting, it’s pretty common and (usually) a very normal part of the early weeks.

If your baby is still consistently unsettled at bedtime after 6 weeks, following our nap and feeding routines in our Newborn Sleep Guide  will help ensure you’re getting their day rhythm right to foster easy bedtimes and great settled nights. 

Creating a Safe and Sleep-Ready Environment

A calming, consistent sleep space can do wonders for your baby’s ability to fall - and stay - asleep. This doesn’t need to be overly complicated or expensive. Think simple, practical steps that create predictability and comfort.

Swaddling and the Moro Reflex

The Moro reflex, or startle reflex, is an automatic response in newborns that can cause their arms to fling out suddenly when they feel a shift in position, hear a loud noise, or experience a sudden sensation. It’s completely normal but can be quite disruptive to sleep.

That’s where swaddling comes in. A snug swaddle mimics the secure feeling of the womb and helps prevent your baby from startling themselves awake mid-nap or in the early stages of settling. Just remember, once your baby shows signs of rolling, it’s time to transition to a sleeping bag with arms out for safety.

Why White Noise Helps Newborn Sleep

White noise isn’t just trendy - it’s incredibly effective. The womb is actually quite a noisy place, with the sound of blood flow, digestion, and your heartbeat creating a constant hum. Silence, in comparison, can feel unfamiliar and unsettling.

A consistent white noise machine or track can help recreate that familiar environment and drown out household or external noises. It acts as a cue for sleep and can be a powerful part of your baby’s settling toolkit.

Safe Sleep Recommendations for Newborns

While every parent wants their baby to be comfortable, safety must always come first. Here are the non-negotiables:

• Always place your baby on their back for sleep

• Sleep your baby in a cot or bassinet that meets safety standards

• Never leave anything in their sleep space (no bumpers, pillows, toys, blankets etc)

• Room-share (not bed-share) for at least the first 6 months

These simple steps dramatically reduce the risk of SIDS and help keep your baby safe from other sleeping accidents. Read more safe sleep tips on our blog 7 baby products not safe for sleep. 

When Should I Make the Room Dark for Naps?

In the early days, allowing your baby to nap in a light-filled room can help reinforce the difference between day and night. But by 3 to 6 weeks of age, once you’ve started shaping a more predictable rhythm, a darker room can help signal that it’s time for sleep.

Melatonin, the sleep hormone, is only produced in the dark. So making your baby’s sleep space nice and dark - even for day naps - can go a long way in helping them settle and stay asleep longer. Reserve the use of night lights just for feeding times, and then switch them back off for sleep.

Week-by-Week Newborn Sleep Milestones: What to Expect

Here’s a general guide to how sleep tends to unfold across the first 12 weeks after birth. Use it as a loose framework to help you understand what’s typical for newborn sleep at each stage.

Week One: Your baby will mostly sleep, feed, and repeat. Expect short wake windows (around 45 minutes) and no real difference between day and night.

Weeks 2 to 3: Wake periods begin to lengthen slightly, and your baby may have more alert, engaged moments. This is a great time to introduce consistent sleep cues and a bedtime ritual.

Weeks 4 to 6: This is the peak of the “fussy phase” for many babies. Evening cluster feeding and unsettled behaviour is common. Focus on full feeds, age-appropriate wake windows, and try moving bedtime earlier. Following an age-appropriate routine can help make sleep more predictable and get back to easier settled nights. 

Weeks 6 to 10: Catnapping often emerges now. A dark sleep space, consistent sleep cues and ensuring you have their sleep pressure just right will help lengthen naps again.

Weeks 10–12: Some babies will begin sleeping longer stretches overnight (anywhere between 4 to even up to 12 hours straight). But during the day, you’ll probably find it difficult to successfully transfer them from asleep in your arms to their bassinet without waking them. This is when using sleep associations becomes key in helping them feel content in their sleep space. 

Have a little one under 3 months? 

Our Newborn Sleep Guide is your go-to resource for the first 3 months. This guide helps you build strong sleep foundations from the beginning, avoid common newborn sleep challenges, and feel more confident in the fourth trimester.

“Having this guide from 3 weeks of age has been a life saver. Having something to follow helped me not feel so lost. The routine has been so easy to follow and helped me feel comfortable planning my days. My baby is now 11 weeks old and has just slept 12 hrs straight 3 nights in a row!” Jacqs - Newborn Sleep Guide

“I found Baby Sleep Code on Instagram late one night whilst feeding my 4 week old son. At this time he was sleeping between 8-12 hours total a day and I was struggling to find a routine and have him sleep more. [After getting the guide] we went from a chronically overtired baby to one that happily went off to sleep at his scheduled times within a week. There was no more endless crying as I tried to force a nap and we became the envy of the new mothers group as he started consistently sleeping 15-16hrs a day.” Tara G - Newborn Sleep Guide