Criteria that are commonly used to establish a diagnosis include pelvic pain, infertility, surgical assessment, and in some cases, magnetic resonance imaging. An ultrasound can identify large clumps of tissue as potential endometriosis lesions and ovarian cysts but it is not effective for all patients, especially in cases with smaller, superficial lesions.These studies suggest that endometriosis affects approximately 11% of women in the general population. Endometriosis is most common in those in their thirties and forties; however, it can begin as early as 8 years old. Endometriosis is estimated to affect over 190 million women in their reproductive years.It chiefly affects adults from premenarche to postmenopause, regardless of race or ethnicity or whether or not they have had children. It is primarily a disease of the reproductive years. Incidences of endometriosis have occurred in postmenopausal individuals, and in less common cases, individuals may have had endometriosis symptoms before they even reach menarche.The rate of recurrence of endometriosis is estimated to be 40-50% for adults over a 5-year period. The rate of recurrence has been shown to increase with time from surgery and is not associated with the stage of the disease, initial site, surgical method used, or post-surgical treatment. History
Endometriosis was first discovered microscopically by Karl von Rokitansky in 1860, although the earliest antecedents may have stemmed from concepts published almost 4,000 years ago. The Hippocratic Corpus outlines symptoms similar to endometriosis, including uterine ulcers, adhesions, and infertility.
A 2004 review of studies of dioxin and endometriosis concluded that "the human data supporting the dioxin-endometriosis association are scanty and conflicting", and a 2009 follow-up review also found that there was "insufficient evidence" in support of a link between dioxin exposure and developing endometriosis. A 2008 review concluded that more work was needed, stating that "although preliminary work suggests a potential involvement of exposure to dioxins in the pathogenesis of endometriosis, much work remains to clearly define cause and effect and to understand the potential mechanism of toxicity". Pathophysiology
While the exact cause of endometriosis remains unknown, many theories have been presented to better understand and explain its development. These concepts do not necessarily exclude each other. The pathophysiology of endometriosis is likely to be multifactorial and to involve an interplay between several factors. Formation
The main theories for the formation of the ectopic endometrium-like tissue include retrograde menstruation, Müllerianosis, coelomic metaplasia, vascular dissemination of stem cells, and surgical transplantation were postulated as early as 1870. Each is further described below. Retrograde menstruation theory
The theory of retrograde menstruation (also called the implantation theory or transplantation theory) is the most commonly accepted theory for the dissemination and transformation of ectopic endometrium into endometriosis. It suggests that during a womans menstrual flow, some of the endometrial debris flow backward through the Fallopian tubes and into the peritoneal cavity, attaching itself to the peritoneal surface (the lining of the abdominal cavity) where it can proceed to invade the tissue as or transform into endometriosis.