Patient Care


What is Endometriosis?

The endometrium is the tissue that lines the inside of the womb (uterus). During the menstrual cycle, it increases in thickness in preparation for pregnancy. If that does not occur, the lining is shed. The bleeding that occurs during its shedding is what is known as menses.

Endometriosis is a condition where the endometrium is also found in other areas of the body, usually within the pelvis. Like normal endometrial tissue, it 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 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.

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

What are the signs & symptoms of Endometriosis?

The most common symptoms of Endometriosis include:

  • Painful and or heavy periods
  • Painful intercourse
  • Infertility
  • Other associated symptoms include chronic pelvic pain not related to menses, pre-menstrual spotting

Bowel and bladder symptoms include:

  • 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 such as 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 Endometriosis may be discovered incidentally.

The severity of Endometriosis does not always correspond to the severity of symptoms.

It is difficult to know how common Endometriosis is. However, it is a common condition estimated to affect 20-30% of women of the reproductive age group.

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

How is Endometriosis diagnosed?

Ultrasound 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.

What are the treatment options for Endometriosis?

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 symptomic relief. This involves giving drugs to create a reversible pseudo-pregnancy, or pseudo-menopausal state which can stop ovulation and hence allow the endometrial tissue to regress and die.

Combined Oral Contraceptive Pill

Side effects of this include bloatedness, nausea, vomiting, and weight gain.

Testosterone derivatives

Examples of this include Danazol and Gestrinone. The side effects of this treatment include acne, changes in voice, increased body hair.


Examples of these are Provera, Nor-ethisterone, and Depo-provera. Side effects include bloatedness, weight gain, mood changes, irregular bleeding, and delayed return of fertility. This is especially the case with Depo-provera.

GnRH analogues - create a pseudo-menopausal state

This group of drugs is given in form of injections or nose sprays and are usually used only for short durations (six months). Side effects include menopausal symptoms such as hot flushes, vaginal dryness, and reversible bone loss.

Mirena coil

This can be used to provide relief from 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. As such, 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 diseases such as large cysts, or severe symptoms. Conservative surgery aims to remove and destroy the Endometriotic nodules or cysts. This is usually done by laparoscopy (keyhole surgery), and in rare instances, an open operation or laparotomy. Removal of the uterus (hysterectomy) and the ovaries may be necessary to cure women with severe Endometriosis and who have completed child-bearing.

Find A Doctor

Click here to access our Find A Doctor directory for a list of doctors treating this condition across our NUHS institutions.

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