Endometriosis – Uterine Lining Outside the Abdominal Cavity: Specialists & Information

Endometriosis is a benign but often painful chronic gynecological condition. It involves the growth of uterine lining (endometrium) outside the uterine cavity.

These non-malignant growths of the uterine lining, known as endometriotic lesions, usually occur in the lower abdomen, for example on:

• the fallopian tubes
• the ovaries
• the ligaments supporting the uterus
• the vagina
• the bladder
• the intestines, or
• the peritoneum

In principle, they can also affect other organs in the female body, such as the lungs.

Depending on the severity of the endometriosis, the growths may be as small as a pinhead. However, larger, blood-filled cysts may also form, which can sometimes lead to adhesions in the fallopian tubes and ovaries.

Unlike the endometrium in the uterus, which is shed through the vagina, endometriosis lesions leave tissue behind in the body. This can lead to adhesions and inflammation. As a result, affected women often struggle with infertility.

Endometriosis lesions frequently occur in these areas © Henrie | AdobeStock

Depending on which organs are affected by the uterine lining growths typical of endometriosis, doctors distinguish between three different forms of the disease:

• Endometriosis genitalis interna (internal genital endometriosis)
• Endometriosis genitalis externa (external genital endometriosis)
• Ectopic endometriosis (extragenital endometriosis)

In endometriosis genitalis interna, the growths occur within the uterine muscle tissue.

In endometriosis genitalis externa, the genital areas outside the uterus are affected by growths.

In this form of the disease, endometriotic lesions typically occur in the following areas:

• Outer wall of the uterus
• The uterine ligaments
• In the ovaries
• In the fallopian tubes
• In the so-called Douglas pouch between the rectum and the uterus, as well as
• On the vagina

In extragenital endometriosis, the organs adjacent to the uterus are affected by endometrial tissue growths. 

The following may be affected:

• the intestines
• the bladder, or
• organs outside the pelvis, such as the lungs. However, this type of endometriosis is extremely rare

According to estimates, between 7 and 15 percent of all women of reproductive age suffer from endometriosis. After fibroids, endometriosis is thus the second most common gynecological condition.

In total, between 2 and 6 million women in Germany are affected by endometrial growths. More than 30,000 women are newly diagnosed with this gynecological condition each year. 

Since endometriosis is linked to the menstrual cycle, it primarily affects women between the ages of 20 and 40. In most cases, the symptoms disappear with the onset of menopause.

Endometriosis is also one of the most common reasons for difficulty conceiving.

Many women with endometriosis remain childless against their will © zinkevych | AdobeStock

Despite extensive research, the cause of endometriosis remains unclear. However, there are various theories that attempt to explain how endometrial tissue can grow outside the uterine cavity.

These include:

• the theory of tissue transformation, as well as
• the theory of dissemination

The theory of tissue transformation posits that growths arise from the transformation of one type of tissue or cell into another.

In the case of endometriosis, immature body cells transform into endometrial cells (metaplasia).

The theory of dissemination states that endometrial cells migrate from the uterus to other areas of the body via the bloodstream, lymphatic system, or surgery.

Depending on its location and severity, endometriosis can cause various symptoms and chronic pain. Often, no signs appear for years, so the growths of endometrial tissue remain undetected for a long time in many cases.

Whether, when, and with what symptoms endometriosis occurs depends on a woman’s menstrual cycle and the location of the lesions.

Typical signs of endometriosis include, among others:

• Severe lower abdominal pain and cramps
• Menstrual irregularities
• A bloated abdomen and
• Pain during sexual intercourse

Endometriosis often causes very severe pain during menstruation © Pixel-Shot | AdobeStock

Since hormonal changes during the female menstrual cycle affect endometriosis lesions, symptoms occur shortly before or during menstruation.

If endometriosis lesions are located in the peritoneal cavity between the intestines and the uterus, lower back pain and pain during sexual intercourse may occur.

If endometrial tissue grows into the bladder or intestines, possible symptoms may include:

• Blood in the urine
• Blood in the stool
• Pain during urination or bowel movements, and
• Difficulty emptying the bladder or bowel

Endometriosis can also be a cause of infertility.

If endometriosis is suspected, the first step is a medical history interview. During this interview, the doctor asks the patient about her symptoms. The doctor then performs a gynecological examination. 

During this exam, the doctor palpates the size, position, and mobility of the internal reproductive organs. This allows the doctor to determine whether there are any growths of endometrial tissue in the vagina, on the cervix, or on the ovaries.

For further diagnosis of endometriosis, imaging techniques may be used, such as:

• Transvaginal ultrasound
• Magnetic resonance imaging (MRI) and
• Computed tomography (CT)

These tests help determine the extent of the growths and any changes in the organs.

To definitively diagnose endometriosis, a histological examination of the growths is necessary. A laparoscopy can be used to obtain tissue samples from the growths for subsequent microscopic examination.

Since the cause of endometriosis remains unclear, there is no definitive or curative treatment.

Treatment for endometriosis should therefore aim to remove or reduce the growths and alleviate the patient’s symptoms. Two different treatment approaches are available for this purpose: endometriosis surgery and medication.

Surgical treatment is usually performed using a minimally invasive approach during a laparoscopy, in which the procedure is carried out directly within the abdominal cavity. The goal is to excise as many endometriosis lesions as possible—for example, on the uterus, ovaries, or peritoneum—or to destroy them using laser beams.

Removal of the uterus provides a lasting solution to the symptoms. However, pregnancy is no longer possible afterward, so this procedure is only an option for women who have completed their family planning.

The most advanced drug treatment is ulipristal acetate, which is also used in the treatment of fibroids. The patient is given pain medication to manage the pain that occurs. 

Long-term hormone therapy with a combination of estrogen and progestin (birth control pill) also provides pain relief by causing the uterine lining to shrink.

Certain types of birth control pills lead to an improvement in symptoms for the duration of treatment © zenstock | AdobeStock

• Whether treatment is necessary and which treatment method is used depends on various factors, including:

  • the severity of the symptoms
  • the location of the endometrial growths, as well as
  • the woman’s age and family planning goals

  A combination of medication and surgery can increase the chances of success with fertility treatment.

Endometriosis is not a life-threatening or fatal condition and does not necessarily require treatment. If endometriosis does not cause any symptoms, it does not affect the patient’s quality of life or life expectancy. However, even without noticeable symptoms, it can affect fertility and contribute to infertility.

It is not possible to predict the course of the disease. In some women, endometriotic lesions regress spontaneously.

Treatment often alleviates symptoms. However, after discontinuing medication, symptoms often return after some time (high recurrence rate). 

Even surgery often does not promise a complete cure: in up to 80% of all treated women, endometriosis lesions form again later.

With menopause and the cessation of menstruation, the condition disappears in many women, or their symptoms subside.

Endometriosis specialists are highly qualified gynecologists who care for patients suffering from non-malignant but painful growths of the endometrium outside the uterus.

Endometriosis specialists possess extensive expertise and experience in the diagnosis and treatment of endometriosis.

In doing so, endometriosis specialists always adhere to the strict quality criteria and guidelines for endometriosis treatment defined by professional societies. They collaborate across disciplines with specialists from other relevant medical fields.

Due to their qualifications, endometriosis specialists are found primarily in certified endometriosis centers. Medical facilities that hold the “Certified Endometriosis Center” seal of quality receive an award. 

These are awarded by the Endometriosis Association of Germany e.V., the Endometriosis Research Foundation, and the European Endometriosis League.

To ensure that patients receive optimal care at every stage of their disease, interdisciplinary collaboration among all specialists is essential. 

This interdisciplinary collaboration is best achieved in certified endometriosis centers.

Specialists from the following fields work there:

• Gynecology
• Urology
• Pain management specialists
• Reproductive medicine specialists
• Radiologists
• Pathologists
• Abdominal surgeons and 
• Psychosomatic specialists