How long does depo provera (medroxyprogesterone) wears off the body?

12 months: The contraceptive effect of Depo-Provera lasts 12-13 weeks but after stopping injections it may be as long as 12 months before menses resume.

Months: It takes about 3 months to get out of your system, which is why you have to be very diligent about getting your next shot right around the exact time 3 months after your last one to ensure you have proper birth control protection. And remember to still use condoms because it does not protect you from STDs. Best wishes!