In this animation, we will show what causes menstruation, what is responsible for painful, and sometimes debilitating menstrual cramps.
The uterus is an organ that has thick, muscular walls. Every month the ovaries release an egg into the fallopian tube where it travels towards the uterus. The egg is about the size of a pin head.
The inner uterine wall becomes thickened with nutrients and develops an enriched blood supply. If the egg is not fertilized, the uterus produces a hormone called prostaglandin. This hormone causes the wall of the uterus to contract and expand thus causing the egg and the extra nutrients to be expelled. This is menstruation and can be associated with painful and sometimes debilitating cramps.
traversing through these muscular walls are tiny blood vessels, which supply oxygen and vital nutrients to the muscle tissues. When these muscles contract during menstruation, these blood vessels become constricted. This will reduce the amount of oxygen getting into the muscle tissue. The muscles are literally starved of oxygen. This lack of oxygen is what actually causes pain.