I think I've got too much calcium.
My mother never had a cavity until she was pregnant with me; her first trimester, she got four.
I got my first calcium kidney stone at 12 and have suffered through four since that one. YOW.
A prior doctor told me not to take multivitamins, unless I could find one without calcium in it, which is almost impossible.
There's an old saying, "For every child, a tooth" - a tooth lost that is. I got so many cavities during or right after my pregnancies it wasn't funny.
Mrs VS
I have no problem finding multivitamins without any minerals. Go find a large chain drug store, and ask for help if you have trouble finding plain multivitamins.