Thank you for your question. Taking norethisterone to prepone or postpone periods is safe. You may find that you have left it a little late to finish your period before the 25 th October 2015. Normally you would take the tablets for five days and get a bleed three days after stopping them. If this is the case your alternative choice is to postpone the bleed by continuing to take the tablets as long as you do not want to bleed and expect to bleed three days after you take your last tablet. Hope this helps