My cousin told me the same thing about the doctor saying you'd wake up...I've tried one pillow...maybe I'll try two...but I guess it might not be as big of a deal as I thought...
I just used two pillows... one on each side.... but to tell u the truth it never worked with me, id always end up on my back, my doc told me that if the extra weight was hurting me(laying on my back) i'd wake up before any real damage was done so i stopped worrying about it.