Help with things to say to rude people

Okay, I’m not a confrontational person, so this is a challenge for me. BUT I am getting so tired of people talking about how big I am. I’m due Feb 4 with my 6th child. I get it, you’re surprised when I tell you I’m not due till Feb, but then you pull up your adult pants and stop saying rude things. Tonight a lady just kept on about how big I was, if I only had 1 baby, and she never got that big. I was like, why is she still saying words? Now, I don’t use foul language or anything like that, but any ideas on what I can say to help them understand that they’re being rude without cussing them out would be appreciated. Maybe if I practice a few times I’ll feel like I can say it if someone decides to forget their manners next time. I guess i could just say, “wow, that’s incredibly rude” then turn around and ignore them. Thoughts?