Category: Endometrioma

An endometrioma, also known as a “chocolate cyst,” is a type of ovarian cyst formed when endometrial-like tissue—similar to the lining of the uterus—grows inside the ovaries. It is a specific and often more severe manifestation of endometriosis, a chronic condition where this tissue grows outside the uterus, causing inflammation, scarring, pain, and fertility issues. Endometriomas are filled with old, dark, thick tissue and blood, giving them their nickname due to their chocolate-like appearance on ultrasound or during surgery.

Endometriomas affect up to 40% of individuals with endometriosis, particularly those with moderate to severe forms of the disease. They are most commonly found in women of reproductive age and often appear on one or both ovaries. These cysts are a form of deep infiltrating endometriosis (DIE) and are associated with a higher likelihood of pelvic adhesions, ovarian damage, and reproductive complications.

Causes and Development of Endometrioma

The exact cause of endometriomas is not fully understood, but they are believed to develop when endometrial-like tissue on the surface of the ovary invaginates and forms a pocket that fills with menstrual blood and tissues over time. With each menstrual cycle, the trapped blood accumulates, oxidizes, and turns dark brown. Unlike functional ovarian cysts, which often resolve on their own, endometriomas persist and may grow larger or become more symptomatic without medical or surgical treatment.

Symptoms of Endometrioma

Endometriomas may not always produce symptoms, especially when small. However, as they grow or in combination with other endometriosis lesions, they can cause significant discomfort. Common symptoms of endometriomas include:

• Chronic pelvic pain

• Painful periods (dysmenorrhea)

• Pain during intercourse (dyspareunia)

• Painful ovulation

• Infertility or difficulty conceiving

• Bloating or fullness in the lower abdomen

These symptoms often worsen over time, particularly during the menstrual cycle, and may interfere with daily life and fertility.

Diagnosis of Endometrioma

Diagnosing an endometrioma typically involves a combination of clinical evaluation, medical history, and imaging studies. Transvaginal ultrasound is the most common and effective tool for identifying endometriomas, which often appear as homogeneous, ground-glass cysts. In some cases, MRI may be used to differentiate endometriomas from other types of ovarian cysts or to assess the extent of deep-infiltrating endometriosis.

A definitive diagnosis can only be made through laparoscopy, a minimally invasive surgical procedure that allows for direct visualization and biopsy of the cyst and surrounding tissue. This procedure can also be used to treat the endometrioma if necessary.

Treatment Options for Endometrioma

Treatment for endometriomas depends on several factors, including the size of the cyst, severity of symptoms, impact on fertility, and the individual’s reproductive goals.

• Medical management often includes hormonal therapy (birth control pills, progestins, or GnRH agonists) to suppress the menstrual cycle and reduce inflammation and cyst growth. However, hormonal treatments do not eliminate the cyst and are generally not recommended when actively trying to conceive.

• Surgical treatment, especially laparoscopic excision, is considered the gold standard for removing endometriomas while preserving ovarian function. Surgery may help reduce pain and improve fertility outcomes, but it must be performed by an experienced endometriosis specialist to avoid damaging healthy ovarian tissue.

• Fertility treatments such as in vitro fertilization (IVF) may be recommended for those struggling to conceive, particularly if endometriomas are large, recurrent, or affecting ovarian reserve.