Well, you're wrong about that. I can't even imagine what would motivate such a stance.
BTW, I was pregnant when I graduated -- from law school, and I got a lot of cheers, myself. It is something to be proud of, regardless of whether you're 18, as my mother was, or 34, as I was. Like my mother, I not only finished, I excelled.
And yes, if you try to keep a pregnant woman from participating in a graduation ceremony, I'd be tickled pink to sue you so fast your head will spin, and I'll kick your ass up one side of the courtroom and down the other. ;^)
I guess that language makes you a big girl? Sad to see it, but you are a prime example of being a product of the society you grew up in.
My guess is that you stand on your curb with your children and encourage those recklessly speeding through your neighborhood just in case one out of a thousand drivers is rushing an injured child to the hospital.