So this is the process we call the menstrual cycle. It's the process by which the female individual prepares the uterus for a possible pregnancy, for a possible implantation. But as the case is usually if no if the woman is not sexually active and no fertilization actually takes place, then that leads to the process of menstruation which is categorized by the discharge of the endometrium and the secondary oicide to the outside environment. And this includes the bleeding and the cramping. Now, the final question I want to address is why does the woman feel these pains, the cramping? Well, that's because progesterone doesn't only increase the thickening of that endometrium but it also blocks it inhibits the uterus from contracting.