**1. Introduction**

64 Endometriosis - Basic Concepts and Current Research Trends

Zhu Lan, Lang Jinghe & Wang Hanbi, et al. (2009). Presentation and management of

ISSN 0020-7292

perineal endometriosis. *Int J Gynaecol Obstet*, Vol.105, No.3, (Jun 2009), pp. 230-232,

Endometriosis is a painful chronic disease occurring in 4 to 17% of menstruating women. Its aetiology is unknown, although there is a high incidence in sterile females (10-25%) (Pritts *et al.*, 2003), 60-70% in women with chronic pelvis pain as well as in those who have a family history (Bianchi *et al.*, 2007). It is characterized by the presence of functional endometrial tissue consisting of glands and/or stroma located outside the uterus.

Endometriosis can be divided into intra and extraperitoneal sites. The intraperitoneal locations are ovaries (30%), uterosacral and large ligaments (18-24%), fallopian tubes (20%), pelvic peritoneum, pouch of Douglas and gastrointestinal tract. Extraperitoneal locations include cervical portio (0.5%), vagina and rectovaginal septum, round ligament, inguinal hernia sac, abdominal scars after gynaecological surgery (1.5%) and caesarean section (0.5%). This disease rarely affects extra-abdominal organs such as the lungs, urinary system, skin and the central nervous system (Chapron *et al.*, 2003; Veeraswamy *et al.*, 2010).

Clinical manifestations of endometriosis fall into three general categories: pelvic pain, infertility and pelvis mass. The goal of therapy is to relieve these symptoms. There is no high quality evidence that one medical therapy is superior to another for managing pelvic pain due to endometriosis, or that any type of medical treatment will affect future fertility. Therefore, treatment decisions are individualized, taking into account the severity of symptoms, the extent and location of disease, desire for pregnancy, the age of the patient, medication side effects, surgical complication rates, and cost (Berlanda *et al.*, 2010; Shakiba *et al.,* 2008).
