my dr said that he was going to give me until the end of march to have a period before giving me anything to enduce one. my mirena came out february 22. well, i never had a period, i got pregnant instead. i sincerely urge you to take extra precautions while you are waiting for your period. i feel deep in my heart that the mirena hormones that were left in my body caused me to miscarry my baby may 2. please take extra precautions if you do not want a pregnancy, i would very much hate for you to have to go through the same thing i did. dr's dont know when you will ovulate, so therefore they cant tell you when you will have a period. they will just give you an idea of what the think might happen.