This is according to a report from 9to5Mac in which they discovered that within snippets of iOS 14 code, there are references being made to this new feature. For those wondering what blood oxygen levels are used for, basically if blood oxygen levels dip to a certain point, like 80% and below, it could be a sign of something being wrong.
It could also lead to compromised heart and brain functionality, and having the watch being able to pick up on this could be immensely useful. At this point, it is unclear if newer hardware is necessary to support this feature, meaning that it could be exclusive to the Apple Watch Series 6 and beyond.
In addition to a potentially new feature, 9to5Mac has also spotted signs that Apple could be looking to improve on the ECG feature, where the will upgrade it to help provide more conclusive ECG readings for heart rates between 100 to 120 bpm.