What Happens During a Sleep Study

This content was created by the National Sleep Foundation


Learn what to expect during a sleep analysis at a lab.

If your doctor has referred you to a lab to take a sleep test, chances are you’re a chronic snorer, you have symptoms of sleep apnea (for instance, you temporarily stop breathing during the night), or you feel sleepy during the day even after a full night in bed. Before you go, find out what you should know ahead of time.

Q: What is a Sleep Study?
It's a test that measures how well you sleep and determines whether you have any sleep problems, as well as how severe any sleep problems are. Since people aren’t typically aware of their breathing, movements, and other habits while they snooze, a sleep study will help a doctor examine them while you're in dreamland. Electrodes on wires are attached with paste to your head and body—the process is completely painless—to monitor your brain waves, rapid eye movements, oxygen levels, breathing patterns, respiratory efforts, snoring, muscle tone and leg movements, heart rate, and more.

Q: What Happens When You Arrive at the Lab?
The rooms aren’t as clinical looking as you’d expect, since people need to be able to relax there. Think more along the lines of a hotel room instead of a medical facility—except there are doctor’s offices in the back. There are also video cameras in the room to record everything. To make it comfortable, you can wear your regular pajamas and the temperature is adjusted to your liking. To help you snooze, the room is dark and you can even bring a few personal possessions, like a fan or book to read until you fall asleep.

Q: What if You Can’t Fall Asleep?
The attending tech makes the wires—and everything else—as comfortable as possible to ensure that you will be able to relax and fall asleep, which is necessary for the test. Eventually, almost everyone falls asleep, though it sometimes takes a little more time than usual.

Q: How Long Do I Have to Stay at the Sleep Lab?
Times can vary according to your personal preference, but usually patients arrive between 8:00pm and 10:00pm and leave between 6:00am and 8:00am, for a total of about nine hours, since most labs prefer to get at least seven hours of sleep study time.

Q: What Happens After the Sleep Study?
Just one test typically produces around 1,000 pages of data! A trained professional will analyze all the information, and then a sleep specialist with review your evaluation with you and determine whether you have any sleep problems and, if so, what sorts of treatment options may be best.

Q: What Issues Can a Sleep Study Help You Detect?

A: A sleep test can help determine whether you snore, and if so, how frequently and severely. It can also help a doctor diagnose sleep apnea. A sleep study can monitor your movements to detect any sleep-related seizure disorders or sleep-related movement disorders, such as periodic limb movement disorder. On a more basic level, it can analyze your sleep patterns and help you learn—in more detail—about the quantity and quality of the sleep that you're getting.

If the idea of going to a lab to have people analyze your sleeping habits freaks you out, there might be an alternative. Sometimes a sleep study done by experts is required, but sometimes you can perform a self-test at home using a home sleep study kit. Ask your doctor which is right for you.