Numbness in my legs??

Lately I have noticed that when I lay or sit on one side, the other side goes numb. I have heard of this happening during a pregnancy, but I am not pregnant and I am not all that heavy either (I usually hover around 125-130). Does anyone else experience this? Once I adjust I get the feeling back for a bit before it goes numb again, and the only time I feel it is when I’m sitting or laying down. This may be a bit of a silly question but it happens every night when I try to sleep and I can’t sleep on my back or stomach so i was wondering for those who have, how you dealt with it comfort-wise?