This leaflet is to help you understand what Endometriosis is, how does it happen, what tests you need and what are the long term implications of the diagnosis?

What are Endometriosis and Endometrioma?

Endometriosis is a benign disease that is diagnosed when tissue that is normally found inside the lining of the uterus grows outside instead.  When the tissue grows on an ovary it gives rise to clear demarcated cyst called endometrioma. This cyst contains altered dark coloured blood often referred to as chocolate cyst. In normal course, this blood is produced by the tissues as menstrual blood when inside the uterus.

How does endometriosis happen?

The exact cause of endometriosis remains unknown. The most accepted theory is the so called retrograde menstruation theory. During menstruation, pieces of the inner lining of the uterus arrive in the abdominal cavity through the fallopian tubes and stick to the inner lining of the abdomen or to the ovaries. These endometrial implants develop into endometriotic lesions. The hormone oestrogen is crucial in this process as it is one of the key hormones controlling the menstrual cycle. Genetic and immune factors may also play an important role in the development of the disease.

Should I have more tests done?

You may need more tests depending upon your symptoms and the stage of the disease. If you experience infertility, further investigations may be required to evaluate the extent of the disease or assess your fallopian tubes. In some cases, a blood test can be done to check the ovarian reserve. If you have significant pain, further ultrasound or surgery may be useful.

What does it mean for me in long term?

Long-term prognosis depends on the extent of the disease and size of the endometrioma. Endometrioma up to 3 centimetres in size are usually only watched and do not require surgery. Larger endometrioma are often removed by surgery. On rare occasions, less than 1 chance in 100, a cancer can be found in an endometrioma.

Are there any treatment available?

Treatment can be symptomatic (to relieve the pain), medical or surgical. Wide range of medical treatments are available that aim to decrease the amount of oestrogen in your body. Choice of medication will be based on symptoms. Surgery is often done by laparoscopy (using a small camera and instruments inserted in your abdomen through small holes). It is important to remember that endometriomas tends to recur and often long term treatment is required.

Will it happen again?

Yes, up to half of the women who suffer from endometriomas will require another round of treatment within 5 years. You may be prescribed medication for long term prevention.

What other questions should I ask?

  • Does my endometrioma show signs of cancer?
  • Is it big enough to have it removed?
  • What are the benefits and the side effects of the treatment proposed?

Last updated: September 2019