What’s Really Keeping Your Baby Awake at Night?

They Haven’t Figured Out Night From Day Yet

Newborns aren’t born with a concept of time. Their circadian rhythms, which help regulate sleep and wake cycles, haven’t fully developed. In the womb, they were in a cozy, dark environment, so they didn’t have to distinguish between night and day. When they arrive in the outside world, they’re still on that same pattern, waking up randomly for feeds, comfort, and yes, sometimes just to look around.

The development of their internal clock starts between 6 and 12 weeks, but until then, nighttime might just feel like another nap opportunity. It’s completely normal for babies under 4 months to wake frequently. Over time, environmental cues like natural light, routines, and exposure to regular day and night will help them settle into longer sleep stretches.

Their Sleep Cycles Are Super Short

Babies spend more time in active sleep (REM) than adults, and their sleep cycles are much shorter, about 40 to 60 minutes. Unlike adults, who have longer periods of deep, restorative sleep, babies under 4 months transition frequently between light and deep sleep. These transitions are often when they stir, wake, and need help settling back down.

Active sleep is important for their brain development, but it’s also why they seem to wake so easily. They might startle themselves awake, move around more during light sleep, or simply can’t fall back asleep when they wake between cycles.

Over time, their sleep cycles will lengthen, and they’ll start spending more time in deep sleep, but for now, their wake-ups are a normal part of how their brains develop.

Their Brains Are Growing Faster Than You Can Imagine

During the first few months, your baby’s brain is developing at an astonishing rate. They’re taking in new sights, sounds, and experiences every day and their brains are constantly forming new connections. This rapid development can make sleep more fragmented. When their brains are in overdrive, sleep often gets disrupted and this is known as a developmental leap.

Every time your baby learns something new, like focusing on faces, tracking movement, or recognising your voice, their brain has to process it. Sleep often takes a backseat to all this growth. So even though they might be showing signs of settling into a sleep routine, a sudden developmental phase can throw things off. These disruptions are usually temporary, but they’re an essential part of your baby’s progress.

They Rely on You for Comfort & Security

Babies are born with an innate need to feel safe and connected. In the first few months, they don’t just wake for food or because their sleep cycle ends, they wake because they need you. Whether it’s for a cuddle, to hear your voice, or just to feel your presence, babies wake up because they’re wired to seek comfort from their caregivers.

This is a survival mechanism. Your baby doesn’t know how to self soothe yet and doesn’t understand that it’s safe to be alone. When they wake up and you’re not nearby, it’s instinctive for them to cry out for reassurance. This attachment driven waking is entirely normal.

Over time, as your baby grows more secure in their surroundings and starts to feel more independent, they’ll begin to sleep for longer stretches without needing you as often at night. But for now, those wake-ups are a signal that your baby trusts and needs you, which is actually a great thing.

Their Tiny Tummy Can’t Keep Up

Babies have tiny stomachs that are about the size of a walnut during their first weeks which means they can’t hold much food at once. Whether your baby is breastfed or formula fed, they’ll need to eat frequently to stay full and nourished. Their rapid growth and development also means they burn through those calories quickly, so they wake up every few hours for a refill.

At this age, waking to eat every 2-3 hours is normal and it’s a biological necessity. Their nutritional needs take priority over your need for sleep (sad, but true). As your baby’s stomach grows and their ability to go longer between feeds increases, you’ll gradually notice longer stretches of sleep but right now, waking for feeds is just part of the deal.