The cause of Endometriosis is unknown. The retrograde menstruation theory (transtubal migration theory) suggests that during menstruation some of the menstrual tissue backs up through the fallopian tubes, implants in the abdomen, and grows. Some experts believe that all women experience some menstrual tissue backup and that an immune system problem or a hormonal problem allows this tissue to grow in the women who develop endometriosis.
Another theory suggests that endometrial tissue is distributed from the uterus to other parts of the body through the lymph system or through the blood system. A genetic theory suggests that it may be carried in the genes in certain families or that some families may have predisposing factors to endometriosis.
Surgical transplantation has also been cited in many cases where Endometriosis is found in abdominal scars, although it has also been found in such scars when accidental implantation seems unlikely.
Another theory suggests that remnants of tissue from when the woman was an embryo may later develop into Endometriosis, or that some adult tissues retain the ability they had in the embryo stage to transform reproductive tissue in certain circumstances.
Research by the Endometriosis Association revealed a startling link between dioxin (TCCD) exposure and the development of endometriosis. Dioxin is a toxic chemical byproduct of pesticide manufacturing, bleached pulp and paper products, and medical and municipal waste incineration. The EA discovered a colony of rhesus monkeys that had developed Endometriosis after exposure to dioxin. 79% of the monkeys exposed to dioxin developed Endometriosis, and, in addition, the more dioxin exposure, the more severe the endo.
Provided by the Endometriosis Association