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Mean overnight oxygen saturation

Breathing tests · also printed as Mean SpO2, Mean overnight SpO2, Average SpO2, Mean saturation, Mean SpO2 (overnight)

Typical UK adult range94 % and above

Above 94 percent is typical.

What this test measures

The average blood oxygen saturation across the night, from a finger probe.

Why doctors request it

Part of every sleep study and overnight oximetry, and one of the numbers used when deciding on overnight oxygen.

What commonly pushes it up

Supplemental oxygen

What commonly pushes it down

Sleep apnoea
Lung disease
Obesity affecting breathing
Being at altitude

Everyday reasons for a value outside the range

Probe position and movement affect it
Older people run slightly lower

About the sample

Overnight recording.

Written by a UK consultant physician. Typical UK adult reference ranges; your laboratory's own printed range takes precedence.

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This is an educational summary of results you uploaded. It is not medical advice, a diagnosis or a treatment plan, and it does not replace the doctor who requested the test. If you are worried, or a result is marked outside range, discuss it with your doctor. Written and reviewed by a UK consultant physician. Reference ranges vary between laboratories.