The three weirdest things I've heard as a pregnant woman:

lovesharkweek

(at 4 months) "Are you pregnant, or are you just gaining weight?"

(at 9 months) "Hey!  I didn't know you were pregnant!"

And today (36 weeks) "how far along are you?" my response: I have 4 weeks left! "shouldn't you be in bed?!"  

"no," I respond, not trying to hide my offence, "I'm not sick!"

"But don't pregnant ladies leak fluid or something?"

Now I'm thouroughly offended by her ignorance. "NO! I'm not leaking fluids!" People are dumb.