Recurrence of Endometriosis

The tissue that lines the uterus is known as endometrium. Endometriosis is a chronic condition in which endometrial-like tissue grows outside of the uterus. Endometriosis can lead to pain and heavy bleeding during periods and it can sometimes lead to infertility.¹

Endometriosis affects about 10% of women in their childbearing years, including 70% of women who have painful periods, and 30-40% of patients who have trouble getting pregnant.²

Reoccurance risk factors

It is not uncommon for endometriosis to recur, or come back, after surgery. Recurrence can refer to:³

• A relapse of pain
• The reappearance of endometriosis lesions (detected via ultrasound or surgery)
• A lack of improvement in infertility

Some women experience one type of recurrence, and some women experience several types. Other women do not experience recurrence at all. The chance of recurrence typically increases over time.³

How common is recurrence?

Studies show that between 20% and 40% of women will experience recurrence of endometriosis symptoms within five years of their initial surgery.

As mentioned, one sign of recurrence is the presence of endometriosis following surgery to remove endometriosis lesions. However, these lesions can also be a sign of disease progression, rather than recurrence. For example, if lesions disappear and then re-appear, especially if they are particularly mild, this may be a sign of progression, not recurrence⁴.

Risk factors

Risk of recurrence is very individualized, and often difficult to predict. However, the following factors may increase a woman’s risk of recurrence³:

• Younger age
• Presence of a larger cyst/cysts at surgery
• Higher level of preoperative pain
• Lack of pregnancy
• Previous medical treatment

Differences by type and stage of endometriosis

Research shows that the chances of recurrence can differ by the type and stage of endometriosis. For example, one study found that the 4-year recurrence rate (i.e. the rate of recurrence during the first 4 years after treatment) was highest for deep endometriosis and for ovarian endometriosis, but lower for peritoneal endometriosis.⁴ Another study showed that the 2-year recurrence rate was higher for stage III and stage IV endometriosis, and lower for stage I and stage II.⁴

Research on recurrence

There have been multiple studies about the recurrence of endometriosis after surgery, with significant variation between studies.⁴ However, there are some common themes^3,4:

• If a greater proportion of endometriosis tissues are removed during surgery, the chance of recurrence is lower.
• If the surgeon is more experienced, the chance of recurrence is lower.
• The use of hormone therapies after surgery can help prevent recurrence. For example, the use of an oral contractive, other suppressive hormone therapy, or a progesterone IUD (intra uterine device) may reduce the changes of recurrence of pain symptoms, specifically.

Emerging research

Emerging research suggests that the presence of specific immunological factors in the blood may also predict a person's likelihood of experiencing endometriosis recurrence.⁴ Other research suggests that, in the future, biomarkers could be use to predict and hopefully prevent endometriosis recurrence.³ This emerging research suggests that endometriosis treatment and management could be individualized based on these factors. However, further studies are still needed.