Hi shreya

Menstrual cycle is the regular natural change that occurs in the female reproductive system that makes pregnancy possible.The cycle is required for the prooduction of oocytes , and for the preparation of uterus for pregnancy.The menstrual cycle occurs due to rise and fall of estrogen. This cycle results in thickening of the lining of uterus and growth of egg. The egg is released from an ovary around day fourteen in the cycle. The endometrial lining is shed off along with blood.

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Hello!!

Menstrual cycle happens because of changes in hormones in the body. ... The ovaries release the female hormones estrogen and progesterone . These hormones cause the lining of the uterus (or womb) to build up. The built-up lining is ready for a fertilized egg to attach to and start developing.when this egg doesn't get fertilised it sheds off with the linin of endometrium which cause menstrual flow.

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