About Endometriosis
What is endometriosis?
Endometriosis is a condition in which cells similar to the lining of the womb (the endometrium) are deposited elsewhere in the body. Common places for endometriosis are the ovaries, behind the womb (the pouch of Douglas) and occasionally on the bowel or bladder. Endometriosis has even been found on the lungs, although this is extremely rare.
What causes endometriosis?
The most popular theory is that endometriosis is caused when cells from the lining of the womb go backwards through the fallopian tubes into the pelvis during your period. This process is called retrograde menstruation.
Another popular theory suggests that cells of the lining of the womb are also formed in other parts of the pelvis when the organs are developing in babies - or that normal cells undergo transformation to endometriosis cells at puberty.
Some people have also suggested that the cells from the lining of the womb (the endometrium) may be carried to other parts of the pelvis in the blood supply.
No one really knows for sure which of these theories is correct.
Is endometriosis common?
As it is only possible to diagnose the condition through surgery, it’s difficult to know how many women actually have endometriosis. We estimate that between 1% and 7% of women of childbearing age suffer from the disease to varying degrees.
What are the symptoms of endometriosis?
Common symptoms of endometriosis are:
- Painful periods
- Pain on sexual intercourse
- Pelvic pain
- Pain before or whilst opening the bowels
- Pain when the bladder’s full
- Some ovarian cysts
- Difficulty falling pregnant
The exact symptoms depend on the position and extent of endometriosis. However, it’s also possible for women to have severe endometriosis and have no symptoms at all. On the other extreme, some women have very little endometriosis and yet have severe symptoms. We don’t yet understand why this is the case.
How does endometriosis cause pain?
The endometriosis cells are under the influence of the same hormones as the lining of the womb, so internal bleeding can occur at the same time as your periods.
The endometriosis cells can stimulate inflammation and the formation of scar tissue. This scar tissue can lead to the formation of bands between pelvic organs (adhesions). These reduce the mobility of pelvic organs, cause stretching and with it pain.
Endometriosis on the ovaries can lead to the development of cysts which contain dark brown old blood. Because of the appearance of the contents, these are called chocolate cysts. The swelling caused by chocolate cysts leads to pain.
Does endometriosis cause all pelvic pain?
No. Conditions that affect the bowel and bladder can also cause similar symptoms, as can blocked fallopian tubes, ovarian cysts and adhesions due to infection or following surgery. Disorders of the pelvic floor and the muscles of the lower abdomen can also cause pelvic discomfort. Finally, psychological factors may also play a part in how we respond to pain, as well as occasionally being the cause. It’s important to recognise that pelvic pain can be due to more than one problem.