Basic knowledge on endometriosis (What is it? Why does it occur) How common is it? Where does it develop? How is it diagnosed?


Basic knowledge on Endometriosis

What is Endometriosis?

Endometriosis (as a general definition): It is a disease caused by endometrium tissue that covers the uterus inside and bleeds in each menstrual period, on which embryo is planted, being located in other tissues than uterus somehow. It is seen in women of reproductive ages. It is a disease dependent on estrogen. In other words, it disappears with menopause. Similarly, the purpose of drugs of treatment is also to suppress the ovaries thus the production of estrogen hormone.

Where is it commonly located?

What is endometrioma?

Endometrioma is a formation developed by endometriosis planting in the ovaries and forming a cystic formation. Basically, it is an ovarian cyst. As a result of endometrium tissue plantation in the ovaries, with each menstrual bleeding, these spots bleed into the ovaries and a formation filled with former blood develops. Therefore, a dark brown fluid-filled cyst is formed. These cysts are called chocolate cyst due to its color and viscosity.

You may see contents of the chocolate cyst during an operation below.

 Prof. Dr. Süleyman Engin Akhan

Why does it develop?

There are 7 different theories about why endometriosis occur. The oldest and the most popular one is the theory of Simpson. According to this theory, during menstrual bleeding, a part of the blood which includes endometrium tissue passes from the tubes and leaks into the abdomen. Endometrium tissue sticks to these places and cause endometriosis. As a person who saw many patient with different age and symptoms and operated them, I personally think that all these 7 theories may be correct for different patients.

How common is it?

Although prevalence of this disease amongst women is not surely known, it has been presumed that it is between %3 and %10. In women who were applied laparoscopy by gynecologists in USA and England, %10-25 of them were found to have endometriosis. This rate is %40-69 in women with dysmenorrhea, %20-40 in the ones with infertility problem. During laparoscopic tube ligations, women who had multiple pregnancies were found to have endometriosis in %6-43 in various studies. Any woman who had her first menstrual bleeding has a risk of endometriosis. Familial predisposition to endometriosis is reported by many researchers. None of the conducted studies could show a link between the disease and HLA antigens. It is possible that this disease has polygenic multifactorial heritage.

How is it categorized?

Although a categorization of American fertilization association is present, this categorization is both complicated and not helpful to doctors. We clinicians separate endometriosis as slight, moderate and severe endometriosis.

What are its common symptoms?

  1. Dysmenorrhea: painful menstruation.

  2. Dyspareunia: painful sexual intercourse.

In both cases, there is no link between the severity of pain and wideness of endometriosis. A correlation cannot be found between wideness and pain of the disease. Pain level is actually more related to how deep endometriosis is, meaning degree of invasion.

  1. Infertility: condition of couples not being able to have children.

First of all, you should know that the belief “a woman who is diagnosed for endometriosis cannot have children” is wrong. It is true that endometriosis is common in women without a child. However, it does not mean that they will not have children. As stated above, endometriosis was spotted in %6-43 of women with children..

On the other hand, Verkauf et al. suggested that %38.5 of infertile women and %5.2 of fertile women have endometriosis. Endometriosis is 10 times more common in infertile women compared to control group of sam age and population. What causes this? To begin with, it affects tubes and ovaries and causes adhesions. Thus prevents egg from being caught in tubes after ovulation. With similar reasons, through the cysts it causes in ovaries called endometriomas, it prevents ovulation and development of the egg. With other words, it obstructs pregnancy with mechanical factors.

IF we evaluate the condition according to categorization, speculations towards mild and moderate endometriosis obstructing pregnancy are invalid today. In minimal, mild and moderate endometriosis, it has been showed that %90 of patients got pregnant themselves after waiting for 5 years when the ages of patients are considered. The problem is in severe endometriosis cases. However, in most of the cases successful results are shown through a good surgery and supportive reproductive techniques.

  1. Dysfunctional uterine bleeding: Severe and irregular vaginal bleeding, menstruation. It is especially common in patients with adenomyosis.

  2. Symptoms towards the location of endometriosis:  for example, it may cause intestinal problems due to abdominal adhesions.

How should patients be examined and diagnosis be made?

Either in the West or East, women do not want to have a gynecological examination during menstruation. However, diagnosis of endometriosis can be made through a gynecological examination during menstruation period the best. Because, endometriosis spots are sensitive during this period and they can be identified more easily. This group of patients have a special condition during examination, it must be done in rectovaginal way, thus allowing palpation of ligaments that hold the uterus in place.

The most important diagnostic methods are Transvaginal Ultrasonography 8TVUSG) and Magnetic Resonance (MRI). Especially TVUSG is present in most offices, it is easy to use. There is a typical image of endometrioma in TVUSG. However, endometriosis spots cannot be detected in ultrasonography. MRI is used especially for diagnosis of deep endometriosis spots that cause excessive pain, in cases in which various organs are affected (bladder, intestines) or in case of endometrioma accompanying uterus anomalies. Its problem is that it is expensive. Here, you may see MRI image of a giant endometrioma in a patient I operated later.

Prof. Dr. Süleyman Engin Akhan



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