[Bunny M]

Try constantly heating them up during your session! I use a heating pad (while massaging) for 2 minutes after every 7 minutes of pumping. The heat will promote blood flow and it actually makes my ring marks go away within a few hours...it's great. I never wake up with marks unless I've overpumped. My breasts also feel warm even after its ended.

I'm reading over Wikipedia right now and it says although not completely proven, moist heat is a better conductor of heat to the body than dry heat. So hydronoogling could be your solution!