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What Stage of Sleep Does Insomnia Occur?

by Dale Cudmore | Updated: Jun 01, 2023

Insomnia can refer to difficulty getting to sleep, difficulty waking up, or frequently waking up during sleep.

When referring to insomnia and frequent wakeups, it occurs mainly during stage 1 or REM sleep.

These are the lightest stages of sleep where you’re most likely to wake up.

Stages of Sleep and Insomnia

There are 4-5 stages of sleep, depending on who you ask (1).

There are 3-4 stages of non-REM sleep, plus REM sleep (a separate and special stage).

Stage 1 and REM sleep are the lightest stages, and each stage past them is progressively deeper.

Vivid dreaming occurs during REM sleep.

Short of an emergency situation or annoying alarm clock, it’s extremely difficult to wake up in deep sleep (stages 3+). That’s why people sometimes don’t even wake up when there’s a fire alarm going off.

Frequent Wakeups Occur Mostly In The Early Morning

One other thing you may have noted in that picture of sleep cycles above is that the length of each stage changes during each sleep cycle.

Sleep cycles repeat every 90-110 minutes depending on the individual.

As the night goes on, you spend less time in deep restorative sleep (stages 3+), and more time in lighter stages during each cycle.

That’s why people who are “light sleepers,” who wake up easily during the lighter sleep stages, wake up frequently in the early morning and can find it hard to go back to sleep. These people are more likely to develop early morning awakening insomnia.

Note that dreaming is typically a sign of good sleep, so it's one of the easiest ways to assess your own sleep quality.

How Many Awakenings Per Night is Normal?

Waking up once or twice during the night is normal.

However, if you’re waking up more than that, and having trouble getting back to sleep, that’s a possible sign of insomnia.

It could be due to several reasons:

If it is a sleep or psychological disorder, a sleep study run by a health professional is the best course of corrective action (if you haven’t seen a doctor already).

Medical Disclaimer: The information on is not intended to be a substitute for physician or other qualified care. We simply aim to inform people struggling with sleep issues about the nature of their condition and/or prescribed treatment.

About the authorDale is the founder of Snooze University and a sleep researcher. I overcame my sleep issues and now I'd like to help you do the same by summarizing the latest sleep studies for you.