The diagnosis is generally suspected from the history.

Any cyclical symptom may indicate the presence of the disease. Increasing menstrual pain is a common indication of the development of endometriosis. The pain may prevent normal work or social activities. The pain may be different from the more common form of menstrual pain which tends to decrease as one grows older. The pain may be present both in the middle and sides of the abdomen and may not respond well to drugs such as Naprosyn, the pill or Ponstan.

Pelvic or abdominal pain at ovulation or before the period, tenderness in the lower abdomen, infertility and sexual pain may occur. Bowel and bladder pain particularly around the time of menstruation, more frequent need to empty the bladder and diarrhoea or constipation, particularly around the time of menstruation, may indicate the presence of endometriosis. Tiredness, depression and increasing premenstrual symptoms are common associations of endometriosis.

Menstrual disturbances such as increased or reduced bleeding or change in the nature of the bleeding may also occur. Spotting between periods or more particularly, before the periods, is a common symptom.
TopIn some women, infertility may be the only symptom. The patient is often the best person to judge whether endometriosis is present or not. Once the nature of the symptoms are understood, or the disease has occurred previously, the accuracy of the patient making the diagnosis is high.

The disease often commences in the teens. Unfortunately, diagnosis in young women is often delayed because of difficulty in distinguishing endometriosis from the more common type of menstrual pain due to prostaglandin excess, and the hesitation doctors have in performing a laparoscopy to detect the disease.

Examination is usually normal, although at times nodules can be felt within the vagina in the region of the uterosacral ligaments. Imaging modalities such as CT and MRI are of limited value. The place of ultrasound has changed dramatically. Ultrasound can detect endpometriomas, deep infiltrating endometriomas and bowel endometriosis (in 90%) of cases but only a handful of ultrasound specialists are trained to do this type of ultrasound. In most cases ultrasound is also not very useful. CA125 testing is of virtually no value as it is very non-specific and can be elevated for lots of reasons.

The definitive way to diagnose endometriosis is to perform a laparoscopy, remove some of the affected tissue and look at it under a microscope.