Should medroxyprogestrone bring my period back after a yr of not having periods b/c of birth control?

Probably not: If you're not having periods because you're on birth control pills, that's an effect of progesterone. More Progesterone won't help, but a different pill probably would. If you're now off the pill and not having a period, then Medroxyprogesterone will help give you a period.

Depends: If you're talking about Depo-Provera (medroxyprogesterone) medtoxyprogesterone acetate then no. If you're taking a ten day course (or so) of Provera (medroxyprogesterone) orally, then yes, you should have a withdrawal bleed after finishing the pills.