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.

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.

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