Doctors use an important blood test called a complete blood count, or CBC for short, to measure the number of each blood cell in your blood sample. If the CBC shows a low number of red blood cells, white blood cells, or platelets, your doctor may look at the cells under a microscope.
In a typical menstrual cycle, estrogen made by the maturing ovarian follicle causes the glands to grow and the endometrium to thicken (partly through an increased blood supply).This thickening of the uterine lining is called the proliferative phase of the menstrual cycle.n a typical menstrual cycle, estrogen made by the maturing ovarian follicle causes the glands to grow and the endometrium to thicken (partly through an increased blood supply).
A woman becomes pregnant if the egg is fertilized by a man's sperm cell and attaches to the uterine wall. If the egg is not fertilized, it will break apart. Then, hormone levels drop, and the thickened lining of the uterus is shed during the menstrual period. Day 1 starts with the first day of your period. This occurs after hormone levels drop at the end of the previous cycle, signaling blood and tissues lining the uterus (womb) to break down and shed from the body.