My MIL is a pain where that is concerned, my parents just said don't do any unnecessary ultrasounds and left it at that. My MIL on the other hand is getting on my nerves, when we told her we were pregnant at 10 weeks her reply was "why am I just hearing about this?" I was so pissed off about it!
Then we went to see her at about 17 weeks and she went on and on about how much weight I've gained, and what am I eating (as if she doesn't know I'm pregnant, I've only gained 6lbs anyway).
Then DH called and told her it's a boy, no congrats or excitement, just went on and on about how she thinks it should have been a surprise, and all the damage we probably did to baby's brain with all the radiation from the ultrasound. Really pissed me off, I was like from now on EVERYTHING will be a surprise to you, I'm not going out my way to keep her in the loop anymore. She got to do it her way with her two kids, I will do what I please with mine.