The endometrium is the tissue that lines the inside of the womb (uterus). Endometriosis is a condition where endometrial tissue is found outside the uterus.
Who gets endometriosis?
The exact number of women who develop endometriosis is not known. This is because many women have endometriosis without symptoms, or with mild symptoms, and are never diagnosed.
Investigations to diagnose endometriosis are only done if symptoms become troublesome and are not eased by initial treatments. If symptoms develop they typically begin between the ages of 25-40. Sometimes symptoms begin in the teenage years. Endometriosis can affect any woman. However:
Sometimes it runs in families. Therefore, endometriosis is more common in close blood relatives of affected women.
Endometriosis is rare in women past the menopause, as to develop endometriosis you need estrogen, the female hormone. Estrogen levels fall after the menopause.
The combined oral contraceptive pill (often called ‘the pill’) reduces the risk of developing endometriosis. This protective effect may persist for up to a year after stopping ‘the pill’.
What causes endometriosis?
The exact cause is not known. It is thought that some cells from the womb (uterus) lining (the endometrium) get outside the uterus into the pelvic area. They get there by spilling backwards along the fallopian tubes when you have a period.
The ‘spilt’ endometrial cells then continue to survive next to the uterus, ovary, bladder, bowel, or fallopian tube. The cells respond to the female hormone estrogen, just like the lining of the uterus does each month. Throughout each month the cells multiply and swell, and then break down as if ready to be shed at the time of your period. However, because they are trapped inside the pelvic area, they cannot escape. They form patches of tissue called endometriosis.
Patches of endometriosis tend to be ‘sticky’ and may join organs to each other. The medical term for this is adhesions. For example, the bladder or bowel may ‘stick’ to the uterus. Large patches of endometriosis may form into cysts which bleed each month when you have a period.
What are the symptoms of endometriosis?
Patches of endometriosis can vary in size from the size of a pinhead to large clumps. Many women with endometriosis have no symptoms. If symptoms develop they can vary.
In general, the bigger the patches of endometriosis, the worse the symptoms. However, this is not always the case. Some women have large patches of endometriosis with no symptoms. Some women have just a few spots of endometriosis, but have bad symptoms.
- Painful periods. The pain typically begins a few days before the period and usually lasts the whole of the period. It is different to normal period pain which is usually not as severe, and doesn’t last as long.
- Painful sex. The pain is typically felt deep inside, and may last a few hours after sex.
- Pain in the lower abdomen and pelvic area. Sometimes the pain is constant, but is usually worse on the days just before and during a period.
- Difficulty becoming pregnant (reduced fertility). This may be due to clumps of endometriosis blocking the passage of the egg from an ovary to the fallopian tube
- Other menstrual symptoms may occur. For example, bleeding in between periods.
- Uncommon symptoms include pain on passing poo (feces), pain in the lower tummy (abdomen) when you pass urine, and, very rarely, blood in the urine or feces. Very rarely, patches of endometriosis occur in other sites of the body. This can cause unusual pains in parts of the body that occur at the same time as period pains.
How is the endometriosis diagnosed?
The symptoms caused by endometriosis can be caused by other conditions. Therefore, if any of the above symptoms become persistent then tests are usually advised to find the cause of the symptoms. Endometriosis is usually confirmed by a laparoscopy. This is a small operation that involves making a small cut, in the abdominal wall below the umbilicus. A thin telescope-like instrument (a laparoscope) is pushed through the skin to look inside. Patches of endometriosis can be seen by the doctor.
How can the endometriosis be treated?
Endometriosis can be treated at the time of diagnosis. Endometriosis patches can be cut away (excised) or burned away. Treatment with laparoscopy is more difficult with advanced disease that involves large areas of the rectum or larger lesions.
Advanced laparoscopic surgery for chronic pelvic pains and suspected endometriosis should be performed by a surgeon with the necessary skills and expertise in the resection of such lesions and in an operating room equipped for such a surgery. Care should be taken to perform endometriotic patches as complete as possible. Adhesions (scar tissues) should be completely resected and measures preventing their reformation should be applied. The surgeon should also be prepared to resect endometriotic lesions that may involve other organs.