
Menstrual cycle is the female reproductive cycle that women have from their early teen years until menopause, around age 50. It is the series of changes a woman's body goes through to prepare for a pregnancy. About once a month, the uterus grows a new lining (endometrium) to get ready for a fertilized egg. When there is no fertilized egg to start a pregnancy, the uterus sheds its lining. This is the monthly menstrual bleeding (also called menstrual period) during which a woman bleeds from her uterus (womb) via the vagina. This lasts anything from three to seven days.