Endometriomas: What You Need to Know

Many top doctors came and presented at last month’s Endometriosis Foundation of America‘s annual Medical Conference titled, Pursuing Precision with Passion. Experts in the field discussed at length the controversies and challenges of treating endometriomas.

What are endometriomas?

Dr. Kristin Patzkowsky, Assistant Professor of Gynecology and Obstetrics at Johns Hopkins Medicine, describes endometriomas as an endometriosis cyst of the ovary. Also called chocolate cysts, these can occur on one ovary or both. They affect between 20-40% of patients with endometriosis, many of whom also have stage III-IV disease. A knowledgeable doctor can tell the difference between a cyst and an endometrioma on an ultrasound. Some patients may have endometriomas and be asymptomatic. But many patients experience symptoms similar to those of endometriosis. These may include painful periods, pelvic pain outside of periods, painful intercourse, and in some cases, infertility.

How do endometriomas affect fertility?

Not all patients with endometriosis will experience infertility. But, 30% of patients with infertility have endometriosis. Endometriosis can cause infertility in many ways. Scarring and adhesions caused by the disease can distort the physical anatomy of the patient, making ovulation and fertilization difficult. Dr. Patzkowsky talks about how endometriotic lesions can produce inflammatory agents, causing a toxic environment in the body. This can lead to damage to the egg and uterine lining and adversely affect the ability of the embryo to implant.

Patients with endometriosis who have endometriomas have even greater challenges when it comes to fertility. Dr. Patzkowsky discusses how women with endometriomas, compared to women without, have fewer eggs in the ovarian tissue surrounding the endometrioma, impaired egg maturation, and lower AFC and AMH. Women with endometriomas also tend to have a higher FSH level.

Dr. Pinar Kodaman, Director of Reproductive Endocrinology at Yale Fertility Center, shares how the content of endometriomas is toxic in many ways, causing fibrosis, inflammation, and mechanical disruption of the ovary. The presence of endometriomas on both ovaries has a significant effect on ovarian reserve.

IVF and endometriomas

For patients with endometriomas, IVF is an option, although there are risks to consider. Dr. Kodaman discusses how some patients with endometriomas experience a decreased response to gonadotropins, which can lead to a greater IVF cycle cancellation rate. Depending on the size and location of the endometriomas, retrieval of the oocytes can be difficult. There is also a risk that the endometrioma can be punctured during retrieval causing leakage or a rupture, which can lead to infection. Finally, follicular fluid contamination with endometrioma fluid may contribute to decreased blastocyst hatching and also lower pregnancy rates.

Endometriomas and surgical intervention

If endometriomas are so toxic, it seems like an easy decision to just have them removed. Unfortunately, the solution is not that easy, especially for those who are looking to preserve their fertility. Dr. Kodaman warns that when surgically removing endometriomas, patients run the risk of a significant decline in AMH, inadvertent removal of ovarian cortex with cyst wall, and injury from inflammation, cautery or vascular disruption. These risks increase when removing endometriomas from both ovaries. Patients may even run the risk of ovarian failure and go into early menopause.

The importance of the experience of the surgeon

When thinking about surgically removing endometriomas, Dr. Kodaman stresses that the surgical experience of the doctor is very important. When a careful surgical technique is applied there can be no difference in the number of oocytes and embryos obtained following cystectomy. She also states that laparoscopic cystectomy is the gold standard of treatment. It is associated with the lowest recurrence rate of endometriomas and the highest spontaneous pregnancy rate. While researchers have not conducted studies in older patients, younger patients may initially have a drop in AMH levels after surgical intervention, but levels are back up after a year. Draining an endometrioma is associated with a 30-90% recurrence rate and is not recommended.

Even in the most experienced surgical hands, carefully removing endometriomas can be challenging. Dr. Tamer Seckin, the co-founder of the Endometriosis Foundation of America, agrees that draining an endometrioma is not the proper treatment for a patient. He stresses that the most challenging part of removing endometriomas is removing the cyst entirely without disturbing the ovarian tissue underneath.

Following the removal of endometrioma

After removing the endometrioma, some doctors will try to control the bleeding of the ovarian tissue with electrosurgery. But Dr. Seckin warns that it is important not to use this technique as heating the ovarian tissue can cause damage to the eggs. Instead, Dr. Seckin uses fine sutures to piece back the disrupted ovary. Most importantly, patients with endometriomas often have a deeply invasive disease affecting their pelvic sidewall. They also often can have leg and back pain due to the disease affecting the nerves. Simply, removing or draining the endometrioma will not bring pain relief to these patients. Meticulous excision, removing adhesions, scar tissue, and invasive disease throughout the pelvic cavity, is the best way for patients to get relief.

Endometrioma vs endometriosis

Endometriosis is the overall condition in which endometrial like tissue grows outside the uterus, triggering inflammation and scarring. It can involve the peritoneum, ovaries, bowel, bladder, and supporting ligaments. An endometrioma is one specific form of endometriosis, limited to the ovary, where trapped blood forms a cyst. In short, every endometrioma is endometriosis, but most endometriosis is not an endometrioma. 

The distinction matters for treatment. Peritoneal or deep infiltrating lesions may respond to medical therapy and targeted surgery, whereas an endometrioma raises additional considerations about ovarian reserve, surgical technique, and fertility timing. Imaging helps map both. 

Ultrasound and MRI characterize an endometrioma while also looking for coexisting deep disease. Treatment plans integrate symptoms, cyst behavior, and reproductive goals rather than focusing on the ovary alone.

What to do?

For patients with endometriomas who are struggling with infertility, the path to treatment is not clear. Dr. Patzkowsky reports that results of conception are similar in patients who had surgery and those who did not. ASRM and ESHRE recommend surgery as the gold standard for systematic endometriomas and asymptomatic endometriomas that are 4 cm in diameter or larger. They also recommend that endometriomas with a mean diameter below 4 cm should not be systematically removed before IVF. The age of the patient and their baseline AMH levels should be considered before surgically removing the endometriomas. Both Dr. Patzkowsky and Dr. Kodaman believe that if the patient has significant pelvic pain and/or if the endometrioma appears to be large or malignant in nature, removal is the best practice.

Egg freezing as an option

Dr. Tomer Singer, director of the Egg Freezing Program at North Shore LIJ, stresses that early detection is key for patients with endometriosis. He believes patients should be referred to an endometriosis excision specialist and a reproductive endocrinologist to assess their fertility as soon as possible. Singer wants all gynecologists to assess endometriosis patients’ AMH levels from the start. They should then retest their levels every six months so that patients can make informed decisions about their fertility and maybe choose egg freezing as an option, Singer says. He feels one hurdle to getting excellent care is that it can be hard to find an excellent endometriosis surgeon and a reproductive endocrinologist that will do egg freezing, especially outside of major cities.

Conversation is key

Dr. Patzkowsky stresses that overall thoughtful and thorough conversations need to happen between a patient, their fertility doctor, and an endometriosis excision specialist. What is important to note is that many patients with endometriomas also have disease throughout their entire pelvic cavity. IVF may be able to help the patient achieve their pregnancy goals, despite the endometriomas. However, it is still worth talking to an excision specialist if the patient is having other symptoms of endometriosis. The patient and the excision specialist may decide not to touch the endometrioma. But the disease can be removed throughout the rest of the pelvis, reducing symptoms, improving quality of life, and reducing toxic inflammatory agents in the body, which can help reproductive efforts. Patients are their own best advocates in terms of doing what is right for their bodies.

FAQs

Can you have an endometrioma without endometriosis?

By definition an endometrioma is endometriosis located in the ovary. You cannot have a true endometrioma without having endometriosis. However, some people have an isolated endometrioma with little or no visible disease elsewhere. Others have an endometrioma plus peritoneal implants or deep infiltrating lesions that explain additional pelvic or bowel symptoms. 

Does endometrioma mean I have endometriosis?

Yes. An endometrioma is an ovarian expression of endometriosis, so its presence confirms the diagnosis. What it does not reveal is the full extent or depth of disease. Some individuals have a single stable endometrioma with minimal discomfort. 

Others have coexisting peritoneal or deep lesions that contribute to pain, dyspareunia, bowel or urinary symptoms, or fertility issues. 

Do endometriomas go away?

Endometriomas rarely resolve on their own. Hormonal treatments can reduce inflammation and suppress activity, and the cyst may shrink modestly, but complete disappearance is uncommon. During pregnancy some endometriomas become smaller, yet many persist. Monitoring with periodic ultrasound is reasonable when symptoms are manageable and imaging features are typical. 

Intervention is considered if pain is intrusive, the cyst enlarges, imaging raises concern for an atypical lesion, or fertility planning is affected. When surgery is chosen, meticulous cystectomy aims to remove the cyst wall while preserving healthy ovarian tissue. Drainage without removal tends to recur. Any plan should balance symptom control with protection of ovarian reserve and future reproductive options.

How serious is an endometrioma?

Seriousness varies. Many endometriomas are stable and manageable with medical therapy and monitoring. Potential concerns include chronic pelvic pain that limits daily life, reduced ovarian reserve due to inflammation within the ovary, and mechanical issues during egg retrieval or ovulation. 

Complications such as rupture or torsion are uncommon but can cause acute pain and require urgent care. Decisions are individualized, aiming to control pain, safeguard fertility, and minimize risk.

What is the difference between an ovarian cyst and an endometrioma?

Ovarian cyst is a broad term that includes many types. The most common are functional cysts, which arise from normal ovulation and usually resolve within a few cycles. An endometrioma is a specific cyst caused by endometriosis, filled with old blood and inflammatory debris. On ultrasound, functional cysts are often thin walled and clear, while an endometrioma typically shows a homogenous ground glass interior and may persist across cycles. 

Symptoms also differ. Functional cysts are often silent. Endometriomas more often cause period related pelvic pain, deep pain with intercourse, and fertility challenges. 

Management reflects these differences. Functional cysts are usually observed. Endometriomas may need medical suppression, close follow up, or surgery based on symptoms and goals.