Common sites of endometriosis– Growth of endometrial tissue outside the uterine cavity, associated with infertility, abnormal uterine bleeding, and pain.

Causes and Incidence

The cause of endometriosis is unclear, but the prevailing hypothesis suggests dissemination and implantation of endometrial cells at local ectopic sites via retrograde menstruation through the fallopian tubes and distant sites via the bloodstream or lymphatics. Sites can be anywhere in the body, but pelvic structures are most common. Another hypothesis suggests transformation of coelomic epithelium into endometrium-like glands. A familial history, late childbearing, and mullerian duct abnormalities are predisposing factors. Approximately 25% of women can expect to develop endometriosis. It is seen most commonly during the childbearing years.

Disease Process

After implantation of endometrial cells, primarily on pelvic structures (e.g., the ovaries, ligaments, oviducts, and peritoneal surface of the uterus), the cells grow to form lesions. These lesions are subject to hormonal cycles and bleed during menstruation, causing irritation and inflammation of the surrounding tissue, leading to fibrosis and adhesions.


The major symptom is secondary dysmenorrhea, although many individuals are asymptomatic. Other symptoms are abnormal uterine bleeding, dyspareunia, infertility, lower abdominal pain, nausea and vomiting, and pain associated with a full bladder or with defecation.

Potential Complications

The primary complication is infertility or spontaneous abortion.

Diagnostic Tests

Laparoscopy with biopsy allows visualization and histologic confirmation of the lesions.


Laparoscopy to remove or vaporize lesions; hysterectomy with bilateral salpingo-oophorectomy for intractable pain.

Gonadotropin-releasing hormone agonists, progestins, and antigonadotropic agents to inhibit ovarian function and suppress endometrial growth; prostaglandin synthase inhibitors to relieve dysmenorrhea.

Emotional support for depression, altered body image, and possible infertility.