How long does it take for the pill or Depo-Provera (the shot) to work?
The pill is effective 7 days after you start using it. It basically shuts off your ovaries. As long as you remember to take it at the same time each day you will be protected from pregnancy. The Depo-Provera shot is effective about 24 hours after it is given (within the first five days of your period), even if it is the first time getting the shot. It is important that you talk with your provider, especially with a method change.
