When to go off Depo Provera

I have been on Depo Provera for 10 years now, with no problems.  I am now 49 and wondering when generally, most people start to go off the Depo.  I realize that you probably need to have hormone levels tested, but is there an age when that is recommended?  I believe my mother didn't reach menopause until around 54, but I imagine 10 years of Depo would probably hasten menopause somewhat.

Also, has anyone had any problems after going off the Depo, where there were none before?

Thank you for any input.