Endometriosis: A review of current perspectives and pathophysiology

OBJECTIVE: Endometriosis is a common condition found almost exclusively in women of reproductive age. The literature on endometriosis is extensive, yet its pathogenesis still remains controversial. In this article, we attempt to review the epidemiology, theories of histogenesis, signs and symptoms, pathological features, and new theories relating to the genetics and immunobiology of endometriosis. METHODS: A Medline search was performed, the literature on endometriosis was reviewed, and summary information is now presented. RESULTS: Endometriosis is classically defined as the presence of endometrial glands and stroma outside the uterine cavity and musculature. Endometriosis can manifest itself in several different forms, and it is likely that many different mechanisms are involved in its development. Despite the fact that retrograde menstruation is nearly universal in all women, only some women proceed to develop endometriosis. The most recent evidence to date supports the hypothesis that both genetic changes and immunologic alterations contribute to a woman's susceptibility to and progression of endometriosis. CONCLUSIONS: Despite the extensive amount of literature that has been written, no single theory yet proposed can entirely explain the pathogenesis of endometriosis. Further research must be conducted to better elucidate the pathophysiology of this highly prevalent disorder.