Wait, did I read it wrong? What I got from this is that OP's boyfriend (rather than OP herself) was making comments about her weight and then went on to say about how she'd look good pregnant. But loads of people are saying that OP was "fishing for compliments"...

men can be thougtless and insensitive sometimes. don't worry OP I'm sure ypu are beautiful inside and out and he didn't mean it the way it came out

While you may not be "thin" in his eyes, he's still telling you that you look good.

you must feel like captain obvious.

That's a nice compliment actually. He likes the way you look. He's with you for a reason, and he can appreciate the look of a pregnant woman.

That's a compliment/ insult. I guess he will keep you barefoot & pregnant.

Sounds to me like he has a sense of humour

YDI for having a boyfriend that repeatedly and negatively talks about your looks without being asked since nowhere in the OP does it say you were asking for his opinion or fishing for compliments. If you were asking for his opinion it's still YDI for talking to him about your insecurities as it's rarely ever suited to talk to a guy about anything you're worried, insecure, concerned, etc about that's for your gfs as it seems guys only want their partners to open their mouths to compliment him, initiate/reciprocate sex, or suck their d*ck.

Er... well. He at least tried? You can tell he wasn't trying to be mean

Hot preggo chicks are one in a million, take the compliment