Considering that's the first time you've met her, I don't think that should be her biggest concern at the moment. And regardless, it's kind of rude to point that out, especially out loud and upon just barely meeting you. Hopefully you manage to win her over. Then the hips won't be a focus in her mind.

Well, tell her that she has the wrong attitude to be a grandmother.

Oh great. She's gonna be one of THOSE mother-in-laws, isn't she? The ones that only care about getting grandkids? (Although, anatomically speaking, a wider pelvis is better for childbirth.)

Ha, his mother should do comedy

prove her wrong?

"That's no problem, I used to be a man so we won't be having kids anyway"

I hate this idea that some parents have for their potential daughter in laws, that they have to give them grandchildren. What about being in a loving and secure relationship?

You should have looked her up and down and said"neither do you, but that obviously didn't stop you"

I've got great child bearing hips, looks like I had a few kids too, unfortunately I'm a man.

Is she by any chance suffering from Cranial-Rectal Inversion Syndrome?