What is Menstrual cycle?
[[File:MenstrualCycle2 en.svg|thumb|right|Notice how each graph relates to the others]] The '''menstrual cycle''' is a process that adult [[woman|women]] go through. The menstrual cycle for a woman will repeat every 28 days while they are not [[pregnancy|pregnant]]. During this time, the women's [[Ovary|ovaries]] create a mature [[ovum]] (egg). Then the woman's body prepares for pregnancy by thickening the walls of the [[uterus]]. If the woman [[Fertilization|does not become pregnant]] during this time, the egg and the [[Endometrium|lining of the uterus]] come out of the woman's body during [[menstruation]].<ref name=gov>{{cite web| url=https://www.womenshealth.gov/publications/our-publications/fact-sheet/menstruation.html |title=Menstruation and the Menstrual Cycle Fact Sheet |website=Office on Women’s Health |publisher=United States Department of Health and Human Services |author=Nelson, M.D., Laurence N. |date=December 23, 2014}}</ref> The menstrual cycle process is controlled by four major [[hormones]]: [[follicle stimulating hormone]]; [[luteinising hormone]]; [[estrogen]]; and [[progesterone]]. These hormones prepare the uterus to receive a [[Fertilization|fertilized]] egg and control its development.<ref name=ucsf>{{cite web | url=https://www.ucsfhealth.org/education/the_menstrual_cycle/ | title=The Menstrual Cycle |publisher=The Regents of the University of California |website=University of California San Francisco Medical Center |date=2016}}</ref> The menstrual cycle has three stages: the Follicular stage, Ovulation, and the Luteal (or premenstrual) stage. The cycle will stop if the woman gets pregnant (if a fertilized egg implants itself into the lining of the uterus).<ref name=ucsf/> == Follicular Stage == This stage is the start of the menstrual cycle, and is counted as day one of the cycle. This stage starts when the amount of progesterone and estrogen in a woman's [[blood]] drop. This causes the [[endometrium]] - the thick lining of the uterus - to leave the woman's body through menstruation.