Not getting enough sleep can make you feel tired and moody the next day.
A variety of factors can cause long sleep latency, such as taking frequent naps and experiencing chronic pain.
Risk factors for insomnia include anxiety, an inactive lifestyle, travel, and a variety of other factors.

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You might become frustrated if it takes you a while to fall asleep.
You may alsocycle through fewerstages of sleep.
When Sleep Latency Is Too Short
Short sleep latency means that youfall asleep almost immediately.
This is often a sign of sleep debt, which is the overall effect of not getting enough sleep.
Sleep debt can accumulate over time.
Drinkingalcoholmay also lower sleep latency, as can certain conditions, such asnarcolepsyand idiopathic hypersomnia.
Both of those conditions involve excessive daytime drowsiness, but idiopathic hypersomnia also interferes with the sleep cycle.
Polysomnogram
Thepolysomnogramis an overnight sleep study done at a sleep laboratory or, sometimes, at home.
It is used to diagnose several conditions, including sleep apnea.
In the morning, you’ll be asked to fill out a questionnaire about your sleep experience.
A healthcare provider will reach out with results once they have been interpreted.
MSLTs are performed in a healthcare setting.
Sensors that measure your sleep latency and sleep cycle are placed on your head.
You are then given the chance to take five naps, each spaced two hours apart.
You are woken up 20 minutes into each nap.
A healthcare provider will review the results and contact you to discuss a treatment plan.
It’s given after you’ve already started treatment for a sleep disorder.
It can measure whether you’re too sleepy to perform tasks such as driving or operating dangerous equipment.
Sensors will be placed on your head before the test begins.
When sleep latency is too short, it’s usually due to sleep deprivation.
You may be asked to fill out a questionnaire, such as theEpworth Sleepiness Scaleor thePittsburgh Sleep Quality Index.
Summary
Sleep latency is one of the measures of sleep quality.
Normally, it should take you at least a few minutes to fall asleep when you go to bed.
2016;12(2):263266. doi:10.5664/jcsm.5498
Medline Plus.Sleep and your health.
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American Academy of Sleep Medicine.What is the multiple sleep latency test?
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American Academy of Sleep Medicine.What is a sleep study?
American Academy of Sleep Medicine.Maintenance of a wakefulness test.
RWJ Barnabas Health.When to see a sleep specialist.