Ovarian Endometrioma

Guidelines for Selection of Cases for Surgical Treatment or Expectant Management

Molly Carnahan; Jennifer Fedor; Ashok Agarwal; Sajal Gupta


Expert Rev of Obstet Gynecol. 2013;8(1):29-55. 

In This Article

Nonintervention for Ovarian Endometrioma (Expectant Management)

As previously noted, the risks associated with surgical procedures for ovarian endometriomas are high, and the proper treatment protocol is a matter of debate, especially in women trying to conceive. There are no well-designed randomized control trials using nonintervention as a potential treatment option for endometriomas due to ethical reasons.[82] The European Society of Human Reproduction and Embryology recommends laparoscopic surgery in the treatment of endometriomas that are more than 4 cm in diameter.[83] However, several recent studies (see Table 1), including a meta-analysis by Tsoumpou et al., are promoting a change in the protocol as surgical management does not seem to significantly improve IVF clinical pregnancy rates per cycle compared with no treatment (OR: 1.34; 95% CI: 0.61–1.38). In addition, there is no significant difference in the number of embryos available (WMD: 0.57; 95% CI: -0.27–1.41), oocytes retrieved (WMD: -1.53; 95% CI: -3.23–0.17) and gonadotropin required for stimulation between expectant management and surgical intervention (WMD: 1.55, 95% CI: -9.21–12.31).[82]


One risk that endometrioma patients should be concerned with is cyst puncture during oocyte retrieval. Benaglia et al. reported that 2.8% of patients had a cyst punctured during oocyte retrieval. All patients were given a propholactic antibiotic.[84] Although none of the women developed infections, case studies have reported infection following oocyte aspiration. The women who developed infection required intravenous antibiotics and in one case, bilateral oophorectomy.[85,86] Suwajamkorn et al. found no significant difference between patients with a punctured endometrioma during oocyte retrieval, nonpunctured endometrioma and control patients regarding oocyte and embryo quality. However, the fertilization and pregnancy rates were lower in the patients with punctured cysts.[87] Contamination could potentially affect embryo development and implantation, but more research is needed.

Similarly, spontaneous rupture of the endometrioma is a risk associated with expectant management. As with puncture during oocyte retrieval, infection may occur. In a small case study follow-up 3 years after rupture, three out of 11 women achieved pregnancy, which suggests that rupture does not negatively affect future fertility.[88] In response to COH, Benaglia et al. reported that none of the 58 women who underwent IVF with an in situ cyst experienced spontaneous rupture or pelvic inflammatory disease.[89] A concern among critics of expectant management is the increase in size of an untreated endometrioma during COH. Benaglia et al. found no significant difference in cyst volume before and after IVF–ICSI. However, only ten out of 70 (14.3%) cysts examined were greater than 3 cm, so the conclusion is that IVF–ICSI is safe in endometrioma patients, but should not be overgeneralized to all cases.[89]

If a woman becomes pregnant following IVF–ICSI, some researchers argue that the endometrioma can cause pregnancy complications such as preterm birth, antepartum hemorrhage, placenta complications or pre-eclampsia.[90,91] Other researchers disagree, and have found that pregnant women with endometriosis are not at a greater risk for complications during pregnancy.[29] A recent multicenter retrospective cohort study looking at pregnancy outcomes in women with ovarian endometriomas and women undergoing IVF for other infertility issues found that ovarian endometriomas did not increase obstetrical complications in pregnant women and the live birth rate was not significantly different between the two groups.[92]

Another risk associated with expectant management is the potential to miss a diagnosis of early-stage malignancy. However, only 0.7% of women develop malignancy from endometriosis.[93,94] Van Holsbeke et al. found that CA-125 levels were not useful in distinguishing ovarian endometriomas from other benign ovarian tumors and malignancies, but that color Doppler ultrasound observation of the flow in papillations was useful in premenopausal women. With continued monitoring, malignancies can be detected by an experienced sonologist without surgical removal, with a 0.9% risk of misclassification of malignancies as endometriomas.[12] Tanaka et al. found that the mean diameter of malignant tumors was significantly larger than that of benign tumors (11.2 vs 7.8 cm, respectively).[95] In another study by Tanaka et al., unilateral cysts were more likely to be malignant than bilateral cysts, and in cases of the latter, when one cyst was significantly larger than the contralateral cyst, the woman was at an increased risk of malignancy.[96]