In order to have pregnancy protection for a full year, it is important to schedule your Depo Provera or Depo-subQ Provera 104 shots approximately every 12 weeks. Over the course of a year, you should receive 4 shots.
Your body may go through changes as it adjusts to the progestin provided by Depo Provera. To increase your success with this method, it may be helpful to know what to expect during the first year of use.
Before you begin using the birth control shot, it is important that you are aware of the bleeding side effects that may occur while on this method. Research has shown that women who have been informed about the potential for either irregular (spotting) bleeding or prolonged, continuous bleeding before beginning this method are more likely to continue taking Depo Provera. You should be aware that even though these bleeding effects could be present at the start, according to Pfizer (the manufacturer of Depo Provera), “in clinical trials, over a third of the women had stopped having periods (this is called "amenorrhea") by month 6. By month 12, over half of the women had stopped.” Many women are willing to go through the initial bleeding in exchange for the chance of not having to have a period anymore.