Menstrual cycle

Description

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The menstrual cycle involves cyclic changes in the ovaries, uterus, cervix and vagina over approximately 28 days. It begins at menarche and consists of two phases - the follicular phase where an ovarian follicle develops and ovulation occurs, and the luteal phase where the corpus luteum forms. If pregnancy does not occur, the thickened uterine lining is shed through menstruation marking the start of a new cycle. The cycle involves changes in hormone levels, the development and breakdown of tissues, and variations in the cervix and vaginal environment to prepare for potential pregnancy.