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

Effect of Ovarian Endometrioma on Fertility

Studies have compared IVF outcomes in women with endometriosis with those of women with tubal factor infertility and the results are conflicting. In a meta-analysis in 2002, Barnhart et al. found that endometriosis patients had a decreased pregnancy rate (odds ratio [OR]: 0.56; 95% CI: 0.44–0.60).[2] However, this finding has been contested, and a group of ten university hospitals in Japan found no significant difference in fertilization, cleavage and pregnancy rates between endometriosis and tubal factor infertility patients (Table 1).[18] Compared with other benign ovarian cysts, ovarian endometrioma did not significantly affect pregnancy rates per embryo transfer.[19] Furthermore, in a retrospective study of women with ovarian endometriomas and tubal factor infertility, the groups had similar implantation, pregnancy and live birth rates per cycle. However, the endometrioma patients had higher IVF cancellation rates than the tubal factor infertility patients.[20]

The difference in IVF outcomes between women with endometriosis and endometriomas is also controversial. Two studies found no significant difference in clinical pregnancy rates.[21,22] However, in a recent study looking at Stage III–IV endometriosis with and without endometriomas, Opøien et al. found significantly reduced pregnancy rates per cycle and live birth rates per ongoing pregnancy in women with endometriomas (Table 1).[23]

Predictors of IVF Success in Women with Endometrioma

Ovarian reserve is defined as a woman's total ovarian follicle pool, which includes the primordial and growing follicles. In general, ovarian reserve declines with age, and a low ovarian reserve is associated with a decreased chance of pregnancy.[24] However, there is no single biomarker that can accurately estimate a woman's ovarian reserve. In an IVF patient, a woman's response to controlled ovarian hyperstimulation (COH) is thought to be an accurate measure of ovarian reserve since a poor response is associated with fewer embryos available for implantation and reduced pregnancy rates.[25,26] Some authors argue that the current predictors of ovarian response are adequate for predicting the quantity, but not the quality, of oocytes and pregnancy outcomes.[27] Three factors are used to help to predict a woman's response to COH during an IVF cycle: levels of day 3 follicle-stimulating hormone (FSH), the antral follicle count (AFC) and more recently, levels of anti-Müllerian hormone (AMH).[26]

Traditionally, basal FSH is measured on day 3 of a woman's menstrual cycle. It is believed that women with a good ovarian reserve have lower levels of FSH because the ovary produces enough hormones (estrogen) to further inhibit production of FSH. FSH levels above 10 IU/l have a high specificity for predicting a reduced response to COH (80–100%), but the sensitivity for actually identifying these women is low (10–30%).[26] While there is no general consensus on the predictability of FSH on IVF outcomes, Abdalla et al. found that women with higher levels of FSH produced significantly fewer oocytes (and thus embryos) for transfer than women with moderately elevated FSH levels. They also reported that higher FSH levels are a good quantitative, but not qualitative measure of ovarian reserve.

Although pregnancy rates and live birth rates decrease as levels of FSH levels increase, live births are still possible in patients with elevated FSH levels (>20 IU/l), especially in younger women.[28] In one study, women who had in situ endometriomas or prior surgery for endometriomas had significantly higher FSH levels than a control group of women undergoing IVF for male factor infertility. However, this study did not compare the FSH levels of women with in situ endometriomas from those with prior surgery.[29] As seen in Table 2, Bongioanni et al. reported no significant difference in FSH levels between women with in situ endometriomas, prior surgery for endometriomas and women with tubal factor infertility.[20]

The AFC is calculated via transvaginal ultrasound and is used to predict ovarian response and the number of oocytes that can potentially be retrieved in IVF. In patients with a reduced AFC, specificity was high (73–100%) and sensitivity was low (9–73%) for a poor response to COH. Furthermore, specificity was high (64–100%) and sensitivity low (8–33%) for failure to conceive.[26] As seen in Table 3, a study by Barri et al. compared women with ovarian endometriomas and women undergoing IVF for male factor infertility and found that the endometrioma patients had a significantly lower AFC than the control group.[29] Other benign ovarian cysts do not negatively affect AFC, but in women with a unilateral endometrioma, the AFC was significantly lower in the affected ovary than in the contralateral unaffected ovary.[30]

A new proposed measurement of ovarian reserve and predictor of ovarian response is AMH. The level of AMH is suggested to predict the primordial follicle pool.[31–33] AMH levels correlate with age, decreasing from pre-pubescent years until menopause.[34] In women with low levels of AMH (0.2–0.7 ng/ml), specificity was high (78–92%) and sensitivity was moderate (40–97%) for a poor response, but no significant correlation for pregnancy was found.[26] Another study found conflicting results and reported that increased serum AMH levels prior to IVF treatment were associated with a higher oocyte yield and higher live birth rates.[35] However, when oocyte yields were accounted for, AMH was no longer a significant predictor of the live birth rate, indicating that AMH is not a good predictor of oocyte or embryo quality.[32]

In one study, AMH levels were not significantly different between patients with and without endometriosis.[25] However, most studies do not agree with this finding. In a retrospective study, Yoo et al. found serum AMH levels to be significantly lower in women with endometriosis.[36] This finding is supported by Hwu et al. who found that the mean serum AMH level was significantly lower in women with endometriomas than in those without. Furthermore, Hwu et al. found significantly decreased levels of AMH in patients with bilateral endometrioma compared with unilateral disease, indicating that bilateral endometrioma inflicts more damage on ovarian reserve.[37] Yoo et al. also found that AMH was a better predictor of mature oocytes and reduced ovarian response than FSH and age during COH in women with endometriosis.[36] A potential benefit of using AMH compared with other ovarian reserve measures is that AMH levels do not change throughout a woman's menstrual cycle.