The epithelial layer coating the uterine cavity is called endometrium tissue. Endometrium tissue covers the inner wall of the uterus with a thin layer. This tissue, consisting of endometrium cells and stroma cells undergo cyclic changes every month in order to be prepared for pregnancy. During menstruation the endometrium tissue disintegrates and falls apart and is discharged via menstruation blood through the cervix and vagina. However, in most of the women, menstruation blood passes through the tubes and into the abdominal cavity in a small extent. With the retrograde flowing (retrograde) of the menstruation blood, disintegrated endometrium tissue passing into the abdominal cavity are removed by “macrophage" cells belonging to the immune system of the body.

Endometrium tissue goes through regeneration and disintegration phases in a cycle. These cyclic changes occur by the effects of the hormones released from the brain and the ovaries. While endometrium layer is thin after menstruation (3-5 mm), it thickens and reaches to 9-15 mm with the effects of the hormones in the following days. Embryo, forming 5-6 days after the cracking of the oocyte reaches to the uterine cavity. In these days endometrium has to be ready for pregnancy; or else embryo can not settle in uterus and pregnancy can not develop.

Endometriosis is endometrium cells’, forming the inner coating of the womb, settling in other places apart from this area. The places that endometrium cells are located are called 'endometriosis focuses'. These can be few or very common in severe forms.

It is not exactly known how endometrium tissue that should be coating the inner layer of the uterus can settle in other areas. As it is mentioned above, it is established that retrograde flowing of menstruation blood into the abdominal cavity plays an important role. However, though retrograde flowing is present in the majority of women, it is not yet known why some of them develop endometriosis. Deficiency of the immune system is blamed for not destroying the endometrium tissue that reaches the abdominal cavity. As a result, nonperishable endometrium tissue attaches to the outer surface of uterus, ovaries, tubes, sub-abdominal cavity membranes (peritoneum), and intestine surfaces and settle in. While retrograde flow is the most powerful theory in the formation of endometriosis focuses, other mechanisms are also considered to play a role (metplasy theory, hematogenous distribution etc.).

Since endometriosis can be found in women who never have complaints, women conceiving without treatment; the incidence of the disease is not exactly known. Since it is diagnosed by laparoscopy or surgery, reported rations vary. However, it is estimated to be 10% in fertile women. This ratio is lower in women who have no problem in conceiving (1-5%), but it reaches to20-40% in women applying to a doctor due to infertility.

Endometriosis leads to a variety of lesions in the abdomen and on the genital organs. These lesions are classified as Phase I-II-III-IV according to their prevalences. This classification is performed personally during laparoscopy according to the location and the prevalence of the lesions. It is not possible to diagnose endometriosis and estimate its phase without laparoscopy. While in Minimal-Mild (Phase I-II) endometriosis, the disases is limited and in its initiation period, in Moderate-Severe (Phase III-IV) forms it is more widespread. In Phase III-IV, generally advanced adhesions and chocolate cycts are present in the abdomen. Though not always, the complaints of the patient (groin pain, severe aches related to menstruation, pain in sexual intercourse, not conceiving etc.) increases with the phase of the endometriosis proportionally. However, complaints may not be severe in advanced endometriosis and also severe and unbearable complaints can be present in mild forms.

The locations of endometriosis focuses can be seen. It is most frequent in ovaries, and also can be seen in the peritoneum membrane covering the uterus and the Douglas cavity, bonds keeping the uterus in place, tubes, intestines, bladder, cervix, vagina and exterior genital organs. It is rarely located in organs like eyes, lungs other than genitals.

Endometriosis focuses are formations of dark red-blue-black colored, resembling a gunpowder burn. These focuses can remain without change or progress, can lead to infection in those places, draw and adhere to the normal tissues around them (for example uterus and intestines can tightly adhere to each other) or lead to adhesions like thin-thick fibrous bands between the organs. These adhesions may either not lead to any complaint or infertility, or intense adhesions between the tubes and the ovaries make conceiving difficult or totally prevent it. These adhesions may prevent the oocyte from getting into the tube, prevent its journey in the tube or increase the risk of ectopic pregnancy. In addition, deterioriation of the normal anatomical integrity, regression in organs, adhesions or relocations can lead to severe pain. These pains can annoy a woman during a certain period (menstruation, during sexual intercourse) or may be permanent.

A chocolate cyst of 10 cm in diameter, detected in the left ovary during an ultrasound examination (endometrioma).

The most freaquent reasons for application are severe pain and infertility (not conceiving). The complaint of pain can be periodical or permanent. Typical complaints like severe groin pain and/or lumbago (chronic pelvic pain), extremely painful periods (dysmenorrhae), painful sexual intercourse (dispareunia) or pain striking to anus may be present or the patient may complain from atypic complaints. Compliants like irregular periods, constipacy, intestinal obstructions may also be present. However, a chocolate cyst may be detected by routine gynecological and ultrasound examination even though the patient has no complaints.

Infertility (not conceiving) is an important problem effecting patients having endometriosis. These patients can conceive without treatment, but in the advanced phases of the disease, they are generally assisted with surgery or infertility treatments. For the purpose of infertility treatment, induction of the ovulation and insemination are the first choices. Test tube baby application is performed in the next stage for those who can not still conceive. Patients who had undergone laparoscopy or surgery due to chocolate cyst or endometriosis are advised to conceive naturally in the following year. Test tube baby method is applied to the patients who can not conceive via natural ways within this period or patients with advanced problems preventing pregnancy, detected during the operation.

Endometriosis treatment is generally performed due to 3 reasons:

In most of the patients, more than one reason are present. A woman’s being single or married, having children or not, or willing to have baby in the future or not, her age and the intensity of her complaints is important for the selection and the course of the treatment. If she wants to have a baby, sperm analysis of the partner should also be assessed.

There are treatment options that vary among individuals: