When should I stop sleeping on my back? I know you aren't meant to late in your pg but I am looking very pg already and my 12 week scan showed the placenta is right at the front (on top of baby if I am lying on my back). I try and wedge a pillow behind me but always wake up having had the best sleep when I have ended up on my back (must do it while asleep). I'm owrried it isn't good for baby or me.. Any advice anyone? Thankyou