Endometrioma: Causes, Symptoms and Treatment

endometrioma icd 10

Many women suffer from endometriosis. It is a condition in which the tissue that usually lines the inside of the uterus grows out of it.

Endometriosis can cause a lot of pain and even infertility. Another consequence is the formation of endometriomas or cysts in the ovary, which is significantly more painful than a common ovarian cyst, and more difficult to control.

The endometriomas are more likely to form during the reproductive years.

Description and Symptoms

An endometrioma is a pseudo-cyst area, an abnormal occurrence thanks to endometriosis affecting the insides of the ovary.

The type of tissue that makes up the lining of the womb (endometrial tissue) forms something similar to cysts.

These pseudo-cysts gradually grow, absorb blood, and become darker. They can burst, spilling material into the pelvis.

Between 17 and 44% of women of reproductive age who suffer from endometriosis are affected by a cyst, also known as the “chocolate cyst.”

People gave it this name is because the cysts get filled with a brown fluid composed of blood from the endometrial tissue.

Endometriomas come from the endometrial lining that grows outside the uterus and into the ovaries. The accumulation of this tissue forms cysts.

The condition worsens with hormonal changes throughout the menstrual cycle.

These cysts can grow in the ovaries and replace healthy ovarian tissue. As they spread, inflammation and pain develop in the pelvic region.

Endometriomas are more common during the reproductive years, as well as in the left ovary. Some studies had recorded that these cysts can grow to the size of a baseball.

Symptoms of endometrioma include painful periods (dysmenorrhea), pain during sexual intercourse, general pain or aching in the pelvis and lower back, and difficulty in becoming pregnant. Symptoms are likely to cease during the menopause.

Ultrasound scanning and blood tests may be given to diagnose an endometrioma. Other conditions, such as ovarian cysts or tumors, can present similar symptoms.

Endometrioma Causes

Several experts confirmed that an endometrioma forms in an ovary when endometrial tissue (the tissue that makes up the lining of the womb) finds its way to the ovary.

Sometimes part of the menstrual flow goes up via the fallopian tube towards the ovary, a process called retrograde menstruation. Although retrograde menstruation is frequent in women, it does not always result in an endometrioma forming; the reasons are not yet clear.

Other causes of endometrioma have been suggested, but have not yet won general acceptance.


Symptoms of an endometrioma are mostly similar to those of a typical ovarian cyst, only more exaggerated. Almost always include:

  • Cramps in the abdomen and pelvis.
  • Painful periods that get worse over time.
  • Pain in the pelvis when urinating or defecating.
  • Pelvic pain with exercise, stretching or bending over.
  • If the ovary twists and loses its blood supply, severe pain can occur.
  • Severe pain, fever, and vomiting with cyst rupture.
  • Spotting or bleeding between periods.
  • Dark vaginal discharge.

If a woman has severe and sudden pain in her pelvis, she should seek immediate medical attention. A ruptured ovarian cyst or torsion of the ovary are medical emergencies.

Treatments for Endometrioma

Painkillers, particularly non-steroidal anti-inflammatory drugs such as ibuprofen, can be used during period pain. They may be the only treatment needed in mild cases.

Contraceptive Pill: Many women find that symptoms lessen if they are using oral contraceptives. Some take the pill to combat an endometrioma, even if they don’t need to do so for contraceptive purposes.

Levonorgestrel-Releasing Intrauterine System (LNG-IUS): This contraceptive device gets placed in the womb. It releases the hormone levonorgestrel.

Periods become much lighter or stop altogether. This method often prevents the development of an endometrioma.

Progestin hormones, such as medroxyprogesterone acetate, are analogs of the hormone progesterone. They can be taken to minimize the symptoms of endometriomas.

These compounds reduce ovulation and may make periods become irregular or cease altogether.

Danazol is a steroid compound used to treat endometriomas. It prevents ovulation and eases the symptoms from endometriomas.

“Masculinizing” side-effects, such as hair growth on the face and acne sometimes occur with this drug.

Gonadotropin Releasing Hormone Agonists (GnRH Agonists) are drugs that end menstruation by reducing estrogen levels. Without hormone stimulation, the pain from an endometrioma usually stops.

The effect is similar to the menopause but is reversible. Leuprorelin and buserelin are examples of these drugs. These compounds are typically given by injection, or via a nasal spray since they are not suitable for oral dosing.

They should not be used on a long-term basis, since serious side-effects, such as bone-thinning may result.

Female hormones are sometimes given at the same time, to minimize the side-effects of GnRH agonists.

Surgery is often used to remove an endometrioma. If a woman does not wish to have any more children, doctors can remove the whole ovary.

More often than not, they merely take the endometrioma out, usually using key-hole surgery techniques. However, damage to the ovary can still occur.

There is some controversy as to whether surgery to remove endometrioma increases or decreases the chance of subsequent pregnancy.

It seems that the short-term chances of pregnancy may increase, but in the longer term fewer eggs may be produced than would be otherwise.

A woman who wishes to have children should carefully discuss their surgery options with their physician. IVF may be a possible option, but there is some evidence that it is more likely to be successful if people avoid surgery.

How can an ovarian endometrioma affect fertility?

Endometriosis that grows in the ovary and forms endometriomas may prevent the ovary from forming eggs suitable for fertilization.

That is, the eggs can be released from the ovary, but the sperm cannot penetrate their walls.

On the other hand, the fallopian tubes can develop scars due to endometriosis, and this interferes with the passage of the eggs and the spermatozoa. It can also lead to an increased risk of tubal (ectopic) pregnancy.

Because endometriosis is affected by reproduction hormones, an interruption in hormone balance may occur.

This, in turn, can prevent a fertilized egg from being implanted in the uterine wall and consequently a miscarriage.