Endometriosis (pronounced end-oh-mee- tree-oh-sis) is a condition where the cells that
are normally found lining the uterus are also found in other areas of the body but usually
within the pelvis. Each month this tissue outside of the uterus, under normal hormonal
control, is built up and then breaks down and bleeds in the same way as the lining of the
uterus. This internal bleeding into the pelvis, unlike a period, has no way of leaving the
body. This leads to inflammation, pain and the formation of scar tissue. Endometrial
tissue can also be found in the ovary where it can form cysts, called 'chocolate' cysts.