Yea I would definitely be up front with him. Try to compromise as well so he doesn't feel neglected. He has to understand ur hormonal and uncomfortable. Wish you well!
Sometimes being blunt is the best. You can always fall back on the hormones thing if you really hurt his feelings. I didn't want to be touched at all when I first got pregnant, and I'm just plain happy with no contact still. Do try and be patient with him, but if he doesn't get the point, tell him in no uncertain terms. Lol