HI im about to start taking norethisterone to delay my period as i am going on holiday at the end of the week, but i am unsure when my period is due to start, it could be due to start as early as tomorrow. if i start taking the norethisterone today and my period starts tomorrow do i risk having heavier or unusual bleeding? i realise if it does start tomorrow there is no point contiuing the medication but will taking in now cause on side effects like heavy bleeding? i am a 20 year old