Why does having kids mess up your teeth???

My teeth have never been super aesthetically pleasing unfortunately (lots of years of braces) but they were extremely healthy! Healthy gums, never any cavities, etc. and I just sorta did the bear minimum of brushing twice, not really flossing consistently.

With my first baby my gums bled for like a month straight. Apparently that can happen with pregnancy. By my third kid the enamel is wearing off so badly it’s causing small spots which is mortifying and something I used to have nightmares about! They’ve shifted a bit even with my retainer use. I have exposed roots in one of my top teeth and two of my bottom ones. I’m so embarrassed to see a dentist.