What is endometriosis?

It is a condition which occurs when endometrial tissue (tissue that lines the womb), grows outside the uterus (womb).  These lesions can develop into painful growth in the form of peritoneal endometriosis or endometrioma. It is a hormone dependent condition.


What causes it?

The exact cause of endometriosis remains unclear.  It is widely believed that the backflow of menstrual fluid (via the fallopian tubes) into the peritoneal cavity during menses causes implantation of endometrial tissue.  This is known as the “Retrograde menstruation theory”.  However, researchers have also found that retrograde menstruation is a common occurrence in women yet not all women would develop endometriosis.


There is also other explanation from immunology aspect.  The susceptible woman may be associated with failure of the immune cells whose function is to remove this endometrial debris (from retrograde menstruation). This failure can be due to “defective/dysfunctional” of the immune cells.


Endometriosis has been reported to occur in any part of the woman’s body.  However, the commoner sites are ovary, peritoneal lining around the pelvic region and uterosacral ligaments.


What are the symptoms of Endometriosis?

Any woman who is still menstruating is at risk of developing endometriosis.  The most common symptoms include:

  1. Painful menses (Dysmenorrhea)
  2. Pain during sexual intercourse (Dyspareunia)
  3. Heavy or irregular bleeding
  4. Chronic pelvic pain
  5. Difficulty to conceive (subfertility)



What are the effects of endometriosis?

The pain from endometriosis may cause the women to require painkiller and risk addiction/ dependent on it.  They are also less productive, missing from work and confined to bed during menstrual pain.  Others have reported symptoms of depression and mood swing associated with this condition


Women with endometriosis also can have problem with fertility.   The pain during sexual intercourse (due to distortion of internal pelvic anatomy) can cause anxiety during coitus.


The repeated inflammation process of endometriosis causes adhesion and distortion of the fallopian tube.  Endometrioma also affect the quality of ovarian function.  All these pathological process and infrequent coitus due to pain contributes to difficulty to conceive (subfertility).


How is a diagnosis made?

A typical medical history and pelvic examination findings will probably suggest the diagnosis. However, in order to define endometriosis, a diagnostic laparoscopy is needed.  During laparoscopy, the condition of pelvic organs (uterus, fallopian tubes, ligaments and ovaries) can be assessed, endometriosis lesion and extent of the disease noted.  The severity of disease is scored according to AFS (revised) criteria.



1.  Analgesia (painkiller)

This is usually gives during the acute phase (menstrual pain). It provides useful symptom relief but does not change the course of the disease.  These analgesia can be in the form of oral or injectables.


2.  Hormonal

The hormonal therapy seeks to modify the course of the disease by suppression of the estrogen hormone.  The deprivation of estrogen hormone will shrink the endometriosis lesion.  Some of the hormonal treatment include Danazol, oral contraceptive pills (OCP), progestogen injection (Depo Provera), Progestogen-IUD (Mirena) and GnRH agonist (Lucrin, Zoladex).


3.  Surgery

Conservative approach

Conservative surgical treatment is designed to preserve the ability of a woman to bear children in the future. The approach focuses on removing/ destroying the endometriosis lesion and restores the pelvic anatomy.

 Non- conservative approach

This approach includes the removal of the uterus and ovaries and renders the woman menopausal.  It is the definitive treatment for endometriosis but does not preserve fertility.  Non- conservative surgery should only be considered in woman who does not want to conceive or age more than 40 years (with option of HRT).



Treatment of endometriosis is individualized to the woman’s priority.  The presenting symptom, need to preserve fertility and age are the main consideration when deciding on the treatment choice.


Author: Dr Ng Soon Pheng

Dr. Ng Soon Pheng MD(USM), M.Med (O&G), Fellow Reprod Medicine (Singapore), AM (Mal) Dr. Ng Soon Pheng qualified from University Kebangsaan Malaysia (UKM), Malaysia. After obtaining his post graduate degree, Dr. Ng Soon Pheng continued his clinical fellowship training in the field of IVF in Singapore. He was also the recipient of Yayasan Sultan Iskandar (Johor) Scholarship for the fellowship stint. Dr. Ng Soon Pheng has more than 10 years of working experience in the field of Obstetrics and Gynaecology in the public and university hospital, with special interests in infertility. He was an Associate Professor with the Department of O&G in Universiti Kebangsaan Malaysia (UKM) specialising in infertility. Dr. Ng Soon Pheng is currently Consultant Obstetrician and Gynaecologist with special interests in infertility at Columbia Asia Hospital - Puchong.