The document discusses the menstrual cycle and menstruation. It defines menstruation as the shedding of the uterine lining every month. It describes the typical phases and characteristics of a normal menstrual cycle, including the ovarian and uterine cycles. The four phases are the menstrual, follicular, ovulatory, and luteal phases. Changes in cervical mucus and potential abnormalities are also reviewed. Comfort measures and health education related to menstruation are provided.