Sleeping in a sitting position?

I have a pregnancy pillow and I sleep with a pillow between my legs, plus one extra pillow behind my back for added support and still I wake up throughout the night with extremely sore hips from trying to stay on my side. It's so painful that it's hard to get next to any rest at night. 
I've had to start propping myself up with all the pillows into a seated position and elevate my legs just to get some shut eye and relieve some pressure from my hips. Does anyone else do this or have any other solutions that have worked for them?