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What is Endometriosis

Endometrium is the tissue that lines the inside of the womb (uterus). During the menstrual cycle, it increases in thickness in preparation for pregnancy and, if that does not occur, it is shed off. The bleeding that occurs during the shedding off is what is called as the menses.

Endometriosis is a condition where the endometrium is also found in other areas of the body, usually within the pelvis. Like normal endometrium, this tissue also responds to hormones secreted by the ovary and is built up and shed off the same way. However, unlike the normally sited endometrium, this "internal menses" has no way to get out of the body.

Over time, this process can lead to the formation of 'chocolate' cysts (brownish fluid-filled sacs) in the ovaries or scar tissue and nodules (bumps) around and on the surface of the pelvic organs. Also, sometimes, the internal bleeding from the endometriosis can cause the organs in the pelvis - the urinary bladder, uterus, ovaries, tubes, and the intestines to stick together (adhesions).

Sometimes, the endometrial tissue can grow in the muscle layer of the wall of the womb. This can result in thickening of the wall of the womb. This condition is called adenomyosis.

Endometrial deposits can also be found, in or on the bowel and bladder or at sites remote from the pelvis like operation scars and in the lungs.

Endometriosis is not cancer

Why does it occur? The cause is unknown, but several theories have been put forward. The most widely accepted theory is ‘retrograde menstruation'. According to this, during menses some of the menstrual blood flows backwards into the pelvis through the fallopian tubes. This menstrual fluid has some endometrial cells which implant on the reproductive organs or other areas in the pelvis. These implanted cells cause endometriosis.

Symptoms of Endometriosis

‚ÄčThe most common symptoms of endometriosis include:

  • Painful and or heavy periods
  • Painful intercourse
  • Infertility
  • Other associated symptoms may be: chronic pelvis pain , not related to menses, pre-menstrual spotting.
Bowel and bladder symptoms
  • Pain before, during or after opening bowels
  • Bleeding from the bowel especially during menses
  • Pain during, before or after passing urine
  • Symptoms of an irritable bowel - diarrhea, constipation and colic
The majority of women with the condition will experience some of these symptoms. However some women may have no symptoms at all and maybe discovered incidentally.
The severity of endometriosis does not always correspond to the severity of symptoms.

How common is endometriosis? It is difficult to have an accurate number, however it is a common condition estimated to affect 20-30% of women of the reproductive age group.

Who does it affect? Endometriosis can occur at any time from puberty until the menopause. It is extremely rare, but not unknown for it to be first diagnosed after the menopause.
How is Endometriosis Diagnosed

‚ÄčUltrasound scans, blood tests and internal examinations cannot conclusively diagnose endometriosis. The only way to diagnose endometriosis is by laparoscopy. This is an operation in which a telescope (a laparoscope) is inserted into the abdomen through a small cut in the belly button. This allows the surgeon to see the pelvic organs and identify any endometriotic deposits and cysts.

How is Endometriosis Treated

Unfortunately, there is as yet a cure for the condition. However certain medical therapies or surgery can help. The type of treatment used depends on the age of the patient, her desire for future childbearing and the severity of her symptoms.

Hormonal treatments

Medical treatment can be tried for symptom relief. This involves giving drugs to create a reversible pseudo-pregnancy or pseudo-menopause state which can stop ovulation and hence allow the endometrial tissue to regress and die.

Combined Oral Contraceptive Pill. 

Side effects include bloatedness, nausea, vomiting, weight gain.

Testosterone derivatives  

eg. Danazol, Gestrinone. The side effects include acne, change in the voice, increased hair over the body.


eg Provera, Nor-ethisterone, Depo-provera. Side effects include bloatedness, weight gain, mood changes, irregular bleeding, and delayed return of fertility esp. with Depo-provera.

GnRH analogues - create a pseudo-menopause state

This group of drugs is given in form of injections or nose sprays and is usually used only for short durations eg. 6 months. Side effects include menopausal symptoms including hot flushes, vaginal dryness, reversible bone loss.

Mirena coil

This can be used to provide relief from the symptoms like heavy menses.With the exception of the Mirena Coil, Depo-provera and the oral contraceptive pill, the drugs used to treat endometriosis are not contraceptives and barrier methods of contraception should be used during treatment.


Studies have shown that for patients with infertility resulting from endometriosis, surgery offers a better chance of achieving pregnancy than medical treatments. Surgery is also advised for severe disease eg large cysts or severe symptoms. Conservative surgery aims to remove and destroy the endometriotic nodules and/or cysts. This is usually done by laparoscopy (keyhole surgery) or rarely by an open operation - a laparotomy. Removal of the uterus (hysterectomy) and the ovaries may be necessary to cure women with severe endometriosis and those who have completed child-bearing.
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