Sex during pregnancy

First trimester, I felt it burn in my v. But that eased off.

Second trimester, climaxing makes my uterus feel so tight all day like I have a muscle pull. That is the only time I feel all the walls of my uterus, even at the back. It ain't painful but I don't like it so now I don't want to climax. And yet hubby likes it. What do I do about this?