How the menstruation ?happens??
Menstrual blood differs from the one flowing in our veins in it that it doesn?t coagulate easily. Why then does it begin and stop flowing? - Thanks to unusual spiral arteries.
To understand well how the process of menstruation happens, we need to know that our uterus consists of three layers:
? Perimetrium, the outer, slippery cover, just like the one around the heart, which moisturizes and supports the uterus.
? Myometrium ? ?smooth muscle?, the thickest layer, thanks to which during a pregnancy the uterus? weight increases from 5 dkg to 1 kg, and its size grows a thousand times!
? Endometrium, the inner layer, the uterus lining which absorbs water, mineral salts and other substances, and produces mucus. It consists of three layers, the outer two of which are shed during menstruation, like a snake?s skin.

In our body, in the uterus, there are three spiral arteries which deliver blood to the two outer layers of endometrium. During pregnancy they supply the placenta with blood. A few days before menstruation, their endings lengthen and twist tightly, like a spiral pulled and twisted at the same time. Because of this, the blood flow slows down. 24 hours before the menstruation the spirals shrink and the blood flow stops completely. Without blood ? and hence oxygen ? the tissue of the lining dies. Then, the suddenly closed arteries open equally suddenly and the blood flows under the dead lining, creating bubbles and pockets. The stretched lining bursts and, together with the blood, begins to leave our body ? our menstruation starts ?
During menstruation about 6 spoons of different substances leave our body, half of it is blood and the other half are pieces of lining and vagina and cervix secretions.




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