How long can you be on depoprovera before you have to worry about thinning of the bones. i have been on it for 11+yrs?

Yikes!: The lack of cyclical bleeding really affects bone health as appropriate estrogen and Progesterone balance are what keeps your bones healthy. Since Depo-Provera is a synthetic progestin it interferes with this balance. After 11 years you might consider having a bone density study to check, and i'd give strong consideration to a non-hormonal bc option. Have hormones tested and restored to heal bones.

Not sure: There is no black and white answer concerning osteoporosis (thinning bones) and the use of depo-provera -- but since the fda placed a "black box warning" on depo-provera about it's link to osteoporosis, most physicians now limit it's use to 2 years, unless there are very extenuating circumstances.