There is a layer of mucous membrane on the inside of the uterus (uterine mucosa or endometrium). When these pieces of mucous membrane spread outside the uterus, such as the pelvis or abdominal cavity, it is called ‘endometriosis’. Many women do not suffer from this (and sometimes do not even know that they have endometriosis), but there are also women who experience (severe) pain during menstruation due to endometriosis. You may also suffer from abdominal pain and back pain (specifically: lower back pain), even if you are not having your period. You may also experience fatigue, disturbed bowel movements and problems or pain when urinating (dysuria). A number of women with endometriosis have difficulty becoming pregnant. The disease is not life-threatening. There are effective treatments available in the form of medications and/or surgery. Endometriosis will not go away; it is a chronic condition. It is true that after menopause the complaints usually disappear.
- What is endometriosis?
- Foci of endometriosis
- Focus of endometriosis in the navel
- Cause of endometriosis
- Retrograde menstruation theory
- After the transition
- Symptoms of endometriosis
- Examination and diagnosis
- Gynecological examination
- Follow-up research
- Endometriosis treatment
- Pain relief and hormonal treatment
- Operation for endometriosis
What is endometriosis?
The mucous membrane lining the uterus is called the ‘endometrium’. Uterine mucosa is the covering layer of the inside of the uterus and normally this mucous membrane is only found in the uterine cavity, but with endometriosis, pieces of the mucous membrane have ended up outside the uterus. For example, it is located in the abdominal cavity, on the peritoneum, in the ovaries, on the suspensory ligaments or ligaments of the uterus, between the uterus and the bladder or the rectum or in the intestinal wall. It almost never happens that the mucous membrane is located elsewhere in the body.
Foci of endometriosis
The lining of the uterus thickens cyclically each month as they respond to hormone changes that regulate the menstrual cycle. It is the preparation for a pregnancy; the uterine lining prepares itself for the implantation of an embryo. If you are not pregnant, the mucous membrane layer breaks down again after about four weeks and starts bleeding. During this process, the blood comes out with some mucus. This is called ‘menstruation’. The pieces of mucous membrane that have deposited outside the uterine cavity do the same and follow the menstrual cycle, which consists of the construction phase, ovulation, the maturation phase and menstruation. Every month they grow and become thicker, after which they break off again and start to bleed. Because the blood cannot be drained in this case, it ends up in the abdominal cavity, in the ovary or between the uterus and the bladder or rectum. This can cause all kinds of unpleasant complaints, especially if there are ‘foci of endometriosis’. The blood can spill onto surrounding organs and tissues, causing irritation and leading to inflammation, scarring and adhesions between organs and in the intestines.
Focus of endometriosis in the navel
Endometriosis in the navel, also called ‘Villars nodule’, occurs in only 0.4-4% of women with endometriosis. It may be the only recognizable symptom. Women with a Villars nodule have cyclic swelling and pain in their navel; Roughly half of these women also show bleeding from this swelling.¹
Cause of endometriosis
Retrograde menstruation theory
It is suspected that endometriosis is caused by menstrual blood flowing back through the fallopian tubes to the abdomen during menstruation. This is called the ‘retrograde menstruation theory’. During menstruation, the uterine lining is shed, which is accompanied by vaginal bleeding. Most of the uterine lining is shed through the vagina. However, a small part of the shed endometrium flows through the fallopian tubes to the abdomen and ends up in the free abdominal cavity. This is called ‘retrograde menstruation’, literally translated: ‘returning menstruation’. However, not every woman with retrograde menstruation will also suffer from endometriosis.
After the transition
After menopause the symptoms usually disappear. This is because after menopause the growth and rejection of the mucous membrane stops, causing the parts outside the uterus to stop growing and start to bleed. It is then said that the endometriosis has calmed down.
Abdominal pain due to endometriosis / Source: Leszek Glasner/Shutterstock.com
Symptoms of endometriosis
Endometriosis does not have to cause any complaints. The complaints vary from woman to woman and are related to the places where the uterine lining is located. The mucous membrane changes (outside the uterus) can cause many complaints. These are mainly felt during the menstrual period. This may involve general complaints such as (persistent) fatigue, abdominal pain and back pain (this concerns lower back pain), but you may also suffer from other, more specific complaints. Abdominal pain during menstruation (dysmenorrhea) and prolonged menstruation (menorrhagia) are often seen with endometriosis. Some women suffer from chronic abdominal pain, including between periods. Depending on where the endometriosis is located, you may also experience complaints with defecation (pain when defecating, complaints of diarrhea or constipation and possibly some blood in the stool), or with urination (urination more often than normal with sometimes some blood). Endometriosis can also lead to reduced fertility and pain during intercourse.
Examination by a gynecologist / Source: Doro Guzenda/Shutterstock.com
Examination and diagnosis
If endometriosis is suspected, various tests can be performed to make the diagnosis. It is possible to determine abnormalities through a gynecological examination (internal examination) in which the vagina is looked and felt. The gynecologist can also perform a rectal examination. This is an internal examination in which the doctor inserts a gloved finger into the anus. Any spots of endometriosis between the rectum and uterus can be felt.
Other examinations may include an ultrasound examination. The disadvantage of this is that mild endometriosis cannot be seen during an internal ultrasound examination. Blood tests may also be useful, as a special marker (CA 125) in the blood is increased in endometriosis. A blood test can indicate to what extent the endometriosis is active. Endometriosis can be diagnosed with certainty during a viewing tube operation (laparoscopy). During a diagnostic laparoscopy, the gynecologist can remove a piece of tissue (biopsy) for further examination in the laboratory.
If during a medical examination your gynecologist accidentally discovers small spots of endometriosis that do not cause any complaints, treatment is (usually) not necessary. You may remain under control. In case of extensive endometriosis which may or may not be accompanied by (many) complaints, treatment is strongly recommended.
Pain relief and hormonal treatment
The treatment of endometriosis may consist of pain relief (symptomatic treatment) and hormonal treatment. Because hormones suppress ovulation, there is no build-up of the mucous membrane and menstruation is less. As a result, the complaints often decrease significantly and the endometriosis abnormalities diminish.
Operation for endometriosis
Surgery can also be considered. The gynecologist can remove endometriosis through surgery.
None of the treatment options leads to a permanent cure for endometriosis. Endometriosis is a chronic condition.
- Sadé NS Daal, Freek E. van Slooten and JCM (Hans) van Huisseling. A woman with cyclical bleeding from her navel. Ned Tijdschr Geneeskd. 2014;158:A8104
- Lower abdominal pain: left & right, causes and treatment
- Lower back pain: painful lower back left, right and middle
- Abdominal pain in the lower abdomen: left/right, causes in men and women
- Endometriosis: causes of menstrual pain and pelvic pain
- Dysmenorrhea: severe menstrual cramps or painful periods