I have heard of people doing both at once, however I wouldn't.. I am currently typing laying on my stomach, 3 weeks into my BBL. I doubt you will be able to sleep on only your side. Then again if you are a trooper like that, and you think you can handle it. Go ahead. I just started using my pillow to drive with 2 days ago, other than that I am still keeping off the behind as long as I can.
If you sleep using a bbl mattress, you can.
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