Endometriosis (say "en-doh-mee-tree-OH-sus") happens when tissue that lines your uterus also grows outside your uterus. These growths often attach to the ovaries or other organs, and they may bleed during your period and cause pain. They may also make it hard for you to get pregnant.
Endometriosis can be treated with medicines or with surgery.
eMedicineHealth Medical Reference from Healthwise
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