Home » Patients » Sleep Study
September 2020 |  Reviewed by:  Rafael Sepulveda, MD and Seema Khosla, MD

What is a sleep study?

A sleep study provides a sleep doctor with the most complete evaluation of your sleep. You will be required to stay overnight at a sleep center, hospital or a hotel room.

A sleep study, also known as polysomnography, records your brain waves, heartrate and breathing as you sleep. It also tracks your eye, leg and arm movements, and oxygen levels in your blood. This information will help your doctor make a diagnosis and develop a treatment plan.

Your medical provider or a sleep doctor may recommend a sleep study to:

  • Test for sleep-related breathing disorders including sleep apnea
  • Evaluate abnormal behaviors during sleep due to parasomnias
  • As part of the evaluation of narcolepsy or other hypersomnia-related disorders
  • Adjust the levels of airflow in patients who receive CPAP therapy for sleep-related breathing disorders
  • Determine why treatment for a sleep disorder is not working

For some with suspected sleep apnea, their medical provider or sleep doctor may recommend a home sleep apnea test instead of a sleep study. A home sleep apnea test uses different equipment that you can set up yourself.

A sleep study is the way to ensure that you have the proper diagnosis for a sleep disorder. Speak with your health care provider if you think you might need a sleep study.

How to prepare for a sleep study?

A sleep study involves an overnight stay at a sleep center, hospital or even a special hotel room. These environments are set up to make you as comfortable as possible so you can have a full night’s sleep. Typically, you will not need to report for your sleep study until the early evening.

On the day of your sleep study, you should:

  • Follow your regular routine as much as possible
  • Avoid napping
  • Avoid caffeine after lunch
  • Avoid using hair sprays or ge