This is for anyone out there who may not know how the whole menstruation thing works. The lining of the uterus is called the endometrium. In a normal cycle, the brain produces a hormone called follicle stimulating hormone which causes the egg follicles in the ovary to make estrogen. This causes the endometrium to thicken.
During ovulation, a second hormone called progesterone causes the endometrium to turn spongy. The menstrual period then occurs when the estrogen and progesterone levels fall and the uterus sheds its spongy lining. A normal menstrual cycle lasts for about seven days.
|
