First Stranger Comment

So I work with a ton on 50+ year old men-really really random work demographic. Anyway, yesterday I was standing outside an office waiting to talk to someone and this guy, who is probably in his early sixties, whom I'd never talked to before comes up right next to me (so close that his side was touching my side) and with his rancid breath says to me "Looks like we're having a baby! When are we due" Apparently I was a feeling a bit snotty because I looked at him and told him "I'm due in December...When are you due?"