I have taken a depo-provera shot 3 months back and still not having peroids and i m not pregnant what should i do to have periods?

Wait and see: The Depo-Provera can cause prolonged suppression of menstruation, ovulation. So it may be taking longer then 3 months to 'wear off'. If you don't want to become pregnant - then i would suggest using another form of contraception, just to be safe. You can have thyroid testing and hormone testing to see if anything else may be causing. Irregular periods can be common in 46 year old women.