Unless you have a good reason to do it, I suggest that you refrain from interfering with Mother Nature. Don’t ponder over the question of how to stop your period from coming. I mean, I don’t think it is right to tinker with the normal processes in our body. We all have been taught in school that menstrual cycle is one way in which our body cleans itself. So by stopping your period, you are also denying your own body a chance to rid itself of toxins.
Additionally, even doctors who recommend pills and injections to stop your period from coming readily accept the fact that there are no long term studies done on its effects to your health. But if for any reason related to your health, you must do it, make sure that you talk to your doctor first.