Sometimes women have to clench their muscles to orgasm, or they clench and unclench their muscles because it feels good. Both of those things cause shaking or trembling. I know that happens to me.
I wish I knew the answer to this question! I've been wondering about it for ages. I know that when I'm getting close to orgasm, my legs begin to tremble furiously. My only guess is that the clitoris is so sensitive that when it's stimulated it affects surrounding muscles and tissue. Mind you, that is an absolute shot in the dark, I don't really have a clue! lol
Yeah it started one of the times she was about to orgasm then continued to after we had sex. I was thinking maybe it's just because her legs may have been stretched and stuff in ways she's not used to. I really don't know