Lowest Blood Oxygen Levels Drops During Sleep?

[RXM]

Sporadically I will check on my nights Blood Oxygen levels and whilst they generally are above 90% the entire night I'll get a random few here or there that have plunged to the low 80% range and now recently I've hit 78% on multiple occasions. Just trying to guage how normal this may be. I use a single loop nylon band that keeps the watch perfectly in place and clean it with a microfibre cloth before sleep, opting for the left wrist roughly an inch above the wrist bone. I have a few theories I wanted to throw out there firstly. I do enjoy sleeping with my arm under my pillow. They are orthopedic memory foam but still  I'm thinking I could be cutting off circulation to my arm with the watch during sleep. That or I've got sleep apnea. Or is just normal. I don't have anyone to compare data with so would be interested in knowing what others get. 

[StuartR]

Watches are not medical devices and results are not to be taken as that accurate, if you want an accurate measurement of your blood oxygen levels your better off going to see a doctor..

[RXM]

Thanks. I actually didn't know that at all. All those 999 calls could have been avoided after all.

[RXM]

I'm really only curious, I'm not panicking here. And if there is zero accuracy to the readings then gosh I may as well bin the thing.

[Kene87]

The watch does the same thing as my apple watch and fitbit. Please try not to worry too much 🙂.

[aaadutch]

Hi, I've measured my sleep twice now, the sleep app seems to work quite well. All night was registered and deep sleep 45-50 minutes, sleep score 71-75. My blood oxygen went below 90% for 1.16 minute the first day and for 3.35 minutes the second day. The lowest I hit was 82% so far. I don't think I had sleep apneu, I don't snore much and my build is lean, I'm 53 years old. Or do I? I'm curious to know how much time other people hit levels below 90%. 

[lankyBird]

I am the same age and the same thing has happened to me, nearly identical? This would suggest to me the readings aren't accurate. I was thinking I had serious airway issues but your post has me thinking differently 🤔

[SunflowerSweetie]

If you are sleepy during the day, I'd check with a doctor. I had similar readings and I am not overweight according to BMI. I did a sleep study and was diagnosed with mild sleep apnea which can cause long-term issues if not addressed. 

[aaadutch]

Update: I've measured sleep for more than a week now and I get a bit of below 90% every night, 1 up to 3 or 4 times, 25 seconds up to 4 minutes but then usually there is a dotted line. Sleep score is good though, above 70 usually while for my age (53) 49 is apparently the average. However, i read the Sleep Health Article and noticed that my graph looks just like the A-graph for normal people in the article, a bit better actually, and not at all like the B-graph. The short peaks below 90% are called "transient false recordings" and I've had less of them than in the example. https://www.sleephealthjournal.org/article/S2352-7218(22)00058-4/fulltexthttps://www.sleephealthjour...

[aaadutch]

Thank you SunflowerSweetle. I don't think i'm more sleepy during day time than I ever was.... I would be curious to see what your sleep graphs tended to look like, for comparison. The research in Sleep Health Magazine about the 4 watch suggests that incidental short dips below 90% are transient false recordings...  Here are two of my graphs and the graph in the research that shows a normal person in A and a person with very strong apnea in B. The "normal" person gets below 90% quite a lot.  Curious if yours compared more to person A or person B.