Chocolate cysts, or more generally known as endometriosis, is a topic that is frequently discussed, extensively written about, and widely debated in the scientific community. Despite numerous studies conducted on endometriosis, it remains a condition that medicine has not yet been able to fully explain, and accordingly, a definitive cure has not yet been established. Let us try to understand this intriguing condition through questions and answers:

What is Endometriosis and a Chocolate Cyst?

Endometriosis is the medical term used when the tissue lining the inner wall of the uterus, called the endometrium, is found outside the uterus. If this condition appears as a cyst (a fluid-filled sac) in the ovaries, it is called a Chocolate cyst (Endometrioma) because it contains a thick, melted chocolate-colored fluid.

How does endometriosis occur?

Although there are many theories about how endometriosis develops, there is still no single theory that fully explains its formation mechanism. The currently accepted view is that menstrual blood containing endometrial cells flows backward into the abdominal cavity, combined with certain deficiencies in the immune system that normally clears these cells, resulting in their implantation within the abdomen. Another important factor in the development of endometriosis is the central role of estrogen in the body. Studies have shown that endometriosis lesions can produce their own estrogen, allowing them to continue growing and causing clinical symptoms.

How common is endometriosis?

There are varying data regarding the frequency of endometriosis. It has been reported to occur in 2–18% of women without any symptoms (incidentally), in 5–21% of women with lower abdominal and groin pain, and in 5–50% of women experiencing difficulty becoming pregnant. On average, it is considered to occur in approximately 6–10% of women.

At what ages is endometriosis seen?

Although endometriosis is generally a condition of reproductive age, it can also be detected in teenage girls and in women many years after menopause. The most common age group is considered to be 25–35 years. With the more liberal use of laparoscopy, it has been reported in patients as young as 11 and as old as 78.

Where is endometriosis found?

Apart from the ovaries, endometriosis can be found in many locations, including the peritoneum (the membrane covering abdominal organs), the pouch behind the uterus (Douglas pouch), intestines, the area between the vagina and rectum (rectovaginal septum), as well as in the skin (e.g., episiotomy or cesarean scars), lungs, liver, brain, and even the eyes. The spleen is one of the rare organs where it has not been reported.

What are the known risk factors for endometriosis?

Studies suggest that some individuals have a higher risk of developing endometriosis. These risk factors include:

  • Genetics: Individuals with first-degree relatives (mother or sister) who have surgically confirmed endometriosis have up to 4–8 times higher risk. It is also reported that endometriosis may present more severely in families with a history of the disease. However, no single gene fully explains the condition.
  • Uterine abnormalities (e.g., double uterus, uterine septum)
  • Early onset of menstruation (age 11 or younger)
  • Having no children
  • Short menstrual cycles (less than 27 days)

What reduces or does not affect the risk of endometriosis?

  • Having children reduces the risk.
  • Breastfeeding reduces the risk.
  • Birth control pills reduce the risk.
  • Intrauterine devices do not affect the risk.
  • Tampon use does not affect the risk.

What symptoms does endometriosis cause?

  • Pain
    • Severe menstrual cramps
    • Pain during intercourse
    • Chronic pelvic pain
    • Pain during bowel movements
  • Difficulty becoming pregnant (subfertility)
  • Premenstrual spotting

Why does endometriosis cause difficulty in becoming pregnant?

  • Ovulation disorders or incomplete ovulation
  • Hormonal deficiencies after ovulation
  • Adhesions that may block fallopian tubes or disrupt communication between ovaries and tubes
  • Negative effects on eggs and sperm due to secreted substances
  • Substances from endometriosis lesions may interfere with fertilization
  • They may impair implantation of the fertilized egg in the uterus
  • Pain during intercourse may lead to avoidance

How is endometriosis diagnosed?

The symptoms mentioned above may suggest endometriosis. During examination, deep tenderness, painful masses between the rectum and vagina, or ovarian cysts may be detected. Ultrasonography is useful especially for detecting chocolate cysts but has limited value for peritoneal endometriosis. Laparoscopy (a camera-assisted procedure) is considered the gold standard for diagnosis. Definitive diagnosis is made by microscopic examination of tissue samples.

What treatment options are available?

Since endometriosis is not fully understood, a definitive cure cannot be stated. Treatment is generally symptom-oriented.

  • Medical treatment: There is no complete cure, but symptoms can be reduced. Options include birth control pills, progestins, GnRH analogs, danazol (less preferred today), aromatase inhibitors, and other hormonal therapies.
  • Surgical treatment: Ovarian cysts larger than 4 cm are usually removed surgically. Recurrence rates may reach up to 50% within 5 years. Removing the cyst with its capsule reduces recurrence. In patients with pain, nerve-cutting procedures (LUNA, presacral neurectomy) may help. In infertility cases, removing lesions may increase pregnancy chances. In severe cases, removal of the uterus and ovaries may be considered.
  • New treatments: Hormonal IUDs, selective receptor modulators, aromatase inhibitors, and immunomodulators are under investigation.

Is there a screening or prevention method?

Unfortunately, there is currently no screening or prevention method for endometriosis.

In conclusion, endometriosis is a condition with an unknown cause, commonly associated with pain and infertility, without a definitive medical cure, and with a tendency to recur after surgery. For detailed and individualized evaluation and treatment, consulting a gynecologist is recommended.

Prof. Dr. Ümit İNCEBOZ / Obstetrics and Gynecology Specialist / İRENBE