Anything that involves YOUR vagina is an "ask first" situation.

That's weird. Why would he do that?

Not only is it a little bit disturbing that your husband invited his mother without asking you, but it seems like he's digging in his heels? It would be one thing for him to make the invite thoughtlessly and then realize he was being an a** after you made your feelings known (still not great, but understandable). If he's still insisting on it after you've said it makes you uncomfortable, that's over the line. I realize I'm assuming some stuff here and maybe I'm wrong, but his disregarding your feelings on this is a red flag (if that's what he's doing). You are the patient, and it's *your* privacy that is the concern - he doesn't get to dictate who is or isn't at *your* medical appointments just because he is a father-to-be. It's not the baby's appointment - it's yours.

Very disrespectful!!!! I'd lose my mind and even go as far as rescheduling the appointment and saying they had to reschedule it....my mil will not be at the hospital with me for any reason, we aren't telling anyone when I go into labor.

not disredpectful but inconsiderate

If my husband did that I probably wouldn't even let him go to that one. In my opinion, the appointments are just for you, him, and baby. He can call his mom after and talk to her about it if he needs her support. My doctor won't even allow more than one other person in the room. Maybe that's the case with yours, too. Either way, it's whatever you're comfortable with. In the end it's YOUR appointment, not his.

It's your body you should be the ONLY one to have a say who is there with you

You should tell him that if he wants to disrespect your privacy like that then no one will be going to appointments besides you from now on. He was so out of line.