Happens to me to. I have to either sleep on my bavk or put a pillow under my hip but sometimes that doesnt even help
I like to put a pillow or something in between my legs i think it helps relieve some of the pressure
The only thing that helps me is sleeping on my side and it only helps for alittle bit.
Your.body is preparing for birth the relaxin hormone is being released and your ligaments are stretching it hurts bad try a support belt for when your out and about