Menstrual cycle (menstruation)
The menstrual cycle is the regular natural change that occurs in the female reproductive system (specifically the uterus and ovaries) that makes pregnancy possible. It refers to the series of events that occur in the ovaries of sexually mature and non-pregnant females and culminate in menses. The menstrual cycle is approximately 28 days long. The cycle is required for the production of oocytes. … Read more