Laying on your side while your partner is behind you
Doggy worked best for me. But it also depends a little bit on how big your man is and which way his parts bend/face. No, I'm not asking you to share that information, but I suggest looking it up. Just a thought :)
I have to agree with everyone else here, another one to add would be cowgirl or reverse cowgirl. Anything that involves the preggers lady on top, belly to the floor, or on the side. After the second trimester it’s extremely uncomfortable to be on your back (also horrible for your main arteries and spine)
Doggy with pillows for me lol