A detailed gynaecological history is essential when diagnosing endometriosis. It typically presents with dysmenorrhoea, menorrhagia (heavy regular menstrual periods), as well as deep dyspareunia, ovulatory pain and chronic pelvic pain in advanced cases. Urinary and bowel symptoms are more common in cases of severe endometriosis. A detailed examination is important and this should include a pelvic examination in women who are or have been sexually active. A pelvic ultrasound is an important screening tool for the markers of endometriosis such as endometriomas (ovarian cysts containing endometriosis.
Other endometriosis symptoms include the presence of free fluid within the pouch of Douglas, hydrosalpinges and pelvic tenderness.
Endometriosis has been seen to cluster within families and studies have identified a significant increase in women with an affected first-degree relative. This trend is also evident not only in daughters and sisters with the disease but also cousins. Studies of monozygotic and dizygotic twins have reported the disease to be expressed frequently in both types of twin, as well as exhibiting a similar age of onset compared to non twins sisters. These findings highly suggested a genetic basis for endometriosis with inheritance transmitted as a complex genetic trait.
Endometriosis includes the presence of endometrial glands and stroma outside of the uterine cavity, most commonly within the pelvis. There is peritoneal invasion from the endometriotic foci within the ovaries, peritoneal covering of the uterorectal space (pouch of Douglas) and uterosacral ligaments. This results in a pro-inflammatory response leading to adhesion formation.
Infertility and pelvic pain are two direct effects of endometriotic implant invasion. Abnormal proteolytic activity causes an altered activity of plasminogen activators and fibrinolytic activity. Endometrial implants present within the peritoneal fluid leading to adhesion formation and damage to surrounding, adjacent viscera such as the ovaries, fallopian tubes, uterus and large bowel. There appears to be altered apoptosis within ectopic endometrium leading to prolonged cell survival, increased cell proliferation and adhesion formation.