When tissue that normally lines a woman's uterus grows outside of the uterus, it is known as endometriosis.
At the end of the cycle, this tissue will disintegrate and bleed just like regular uterine tissue does. The blood, however, has nowhere to go. Areas nearby could swell up or become inflamed. Lesions and scar tissue could be present. Your ovaries are where endometriosis is most prevalent. Endometriosis types
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