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  • Writer's pictureAdela

What Causes Baby to be Awake for Hours at Night?

Is your little one waking up in the middle of the night and staying up? For like… hours.

Proven Results for Toddler Sleep Training

What are Split Nights?

If you’re the parent of a baby who’s dealing with segmented sleep, you know exactly what I’m talking about. This isn’t the middle of the night “go in and check on baby until he gets back to sleep” wakeup. This is a full-blown 3:00 a.m. dance party.

It’s got a few names. Segmented sleep, bifurcated sleep, split nights, and it describes a situation where your little one sleeps for a long stretch, then wakes up happy and energetic in the middle of the night, and stays that way for an hour or more.

This is actually a pretty common issue. Baby goes down at 7:30 at night, wakes up at 3:00 in the morning, parties her ass off for an hour and a half, then goes back to sleep, apparently careless about the groggy, miserable day she’s set her parents up for.

Proven Results for Toddler Sleep Training

Why do Split Nights Happen?

There are two major drivers when it comes to sleep. There’s our circadian rhythm, which is our natural tendency to fall asleep when it’s dark and wake up when it’s light. And then there’s our homeostatic sleep drive (aka sleep pressure), which builds up over the time we’re awake.

Over the course of the day, sleep pressure builds up, then at bedtime, when the pressure hits the sweet spot, baby puts her head down and goes to sleep. As that sleep pressure begins to subside, circadian rhythm takes over and baby stays asleep until morning.

In the case of a split night, we could be looking at one of two reasons why they’re waking up.

● Baby’s not getting to bed early enough, OR…

● Baby’s going to bed too early.

Proven Results for Toddler Sleep Training

How to Resolve Split Nights

1. Baby's bedtime is too late

If baby’s getting to bed too late, if too much sleep pressure has built up, the brain has this instinctive response that says, “Hey, you’re tired but you’re not sleeping,” and then starts upping the cortisol levels. So this can make it tough for baby to get to sleep at bedtime, since that cortisol’s got them a little bit jacked, and it can also cause a full wake up at the end of a sleep cycle, which commonly happens around 2 or 3 in the morning.

To resolve this, consider moving bedtime up a bit over the course of a few nights.

Proven Results for Toddler Sleep Training

2. Baby's bedtime is too early

In a situation where baby’s getting lots of quality daytime sleep and going to bed early, it’s possible that there’s not enough sleep pressure built up to keep baby sleeping until their circadian rhythm takes over and helps them sleep through the rest of the night, so up they get. And now that there isn’t as much sleep pressure, and their circadian rhythm doesn’t have the horsepower to get them to sleep on their own, suddenly they’re up and active for an hour (or three!) while that pressure builds back up.

Now, I’m all about early bedtimes. But if your baby’s experiencing this kind of split-night sleep, it’s worth looking at their schedule and doing a little fine tuning to ensure that you’re hitting the optimum sleep pressure right at the same time that baby’s going to bed for the night.

Try to avoid putting baby to bed early more than one or two nights in a row. We want to prevent overtiredness but we also don’t want them in the crib at night for more time than they’re actually capable of sleeping. So if baby’s had a tough day and didn’t nap well, it’s fine to get her to bed a little early, since that sleep pressure is likely already built up, but try to get her back onto the regular schedule starting the next morning, including her wake-up time.

Proven Results for Toddler Sleep Training
Proven Results for Toddler Sleep Training

The more you understand the nuances and know where to make minor adjustments for your baby, the better your baby will sleep, and the less they’ll run into these regressions, setbacks, and interruptions.

One final thing to consider if you’re getting ready to tackle this situation. This is not likely to be an overnight fix. Once baby has gotten into this habit, getting them out of it can take some time. Stay consistent, be patient, and before too long your baby and you will both be enjoying full nights of deep, restful sleep.

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