What this measures
The average blood-oxygen saturation your device estimated across the night, as a percentage, along with how many minutes it managed to sample.
How your device works it out
Light is shone into the skin and the colour of what comes back is read as an estimate of saturation. On a consumer wrist or finger device that estimate moves with fit, skin tone, motion and cold hands, which is why the minutes sampled travel beside the number.
What generally moves it
Altitude, how the device was worn, cold hands, moving in your sleep, and how much of the night the sensor could actually read.
Why Thriverence shows it
It is shown for completeness, with no band and no colour, because it is a number your device produces and you are entitled to see what it holds about you.
What it is not
This is not a pulse oximeter and the figure is not a medical reading. It is not used to diagnose or monitor anything, a low average is not evidence of a condition, and no decision about your health should rest on it. If you are worried about your breathing, the resources below list people to speak to.