Hi, I had an oximetry test done and found that my Oxygen Saturation Level is 77. They are going to put me on oxygen for night time. I sensed a concerned attitude when the person told me about this. When she gave me the test results she did say you know what that means. I foolishly said yes but don't know the first thing about it except the normal Oxygen Saturation Level is between 95 and 100. What causes this? Why oxygen just in the pm? Is this level considered serious? Please fill me in. I am female, 71 yrs. and obese, diabetic, apnea, arthritis. Not in too good shape. I get so out of breath I find it difficult to do anything. Please help. Thank you.