The normal, average duration of menstruation (period) is considered to last from 3 to 7 days. Menstruation that lasts for more than 7 days is called menorrhagia. Menorrhagia can be due to the existence of an endometrial polyp, an endometrial infection, a sub-mucosal myoma or endometriosis. You need a vaginal examination and ultrasound scan to confirm or exclude these possibilities. Functional bleeding from the uterus is also possible. If you haven’t had a period for a long time, you may experience some heavier bleeding at the end. You have to consult your gynecologist about your problem.