Our results showed that in patients with endometriosis being the major indication for IVF/ICSI, the CLBR were similar to controls (non-endometriosis). Although the presence of endometriomahad comparable CLRB, the used gonadotropin dose was significantly higher, and the blastocyst formation ratewas significantly lower compared with those patientswith only endometriosis. In the second analysis, CLBR were comparableacross primary endometrioma, s/p cystectomy and recurrent endometrioma groups. The blastocyst formation rate was significantly higher in the s/p cystectomy group compared with the other two groups.
A number of studies investigated effects of endometriosis on ART outcomes.In general, women with endometriosis have similar ART outcomes to those of controls in terms of LBR [22–24].Our results are compatible with these.Regarding the relationship between the presence of endometrioma and ART outcomes,findings are less consistent. A recent systematic review found women with endometrioma only have fewer oocytes and MII oocytes retrieved when compared tothose without endometriosis, but no such differences in CPR, IR and LBR . Our result is similar to theirs, showing that endometrioma was associated with higher gonadotropin consumption, lower number of oocytes retrieved, and lower blastocyst formation rate, when compared with controls. The final outcome, CLBR, wasthe same as the control group.
When comparing between patients with endometrioma and with endometriosis, our results on outcomes revealed the similarities of LBR and CLBR in patients with endometrioma or with endometriosis. These findings are consistent with previous studies showing similarity in delivery rates and pregnancy rates in patients with unoperated endometrioma and with only endometriosis [26.27]. These studies were however conducted in 2000s, and CLBR was not analyzed.
In comparing primary endometriomaand cystectomy before IVF/ICSI,wefound that although the s/p cystectomy group were younger in age,their ovarian reserves were similar,likely due to surgical excision of endometrioma lowering the ovarian reserve . In our center, our policy is to choose younger patients with moderate ovarian reserve to receive cystectomy for endometrioma for fertility reason.We had encouraged these patients to undergo IVF/ICSI ifnot get pregnancy after trail of one year after operation.Despite concerns of reduced ovarian reserve, surgical removal of endometrioma may improve chances of spontaneous pregnancy by restoring the ovarian functional anatomy.This approach has been considered a primary treatment for infertility in the case of endometrioma . Alsosuch operation improves pain symptoms .Regarding the impact of excised endometrioma on ART outcomes, we found similarities between the primary endometrioma and s/p cystectomy groups interms of the number of oocyte retrieval, number of mature oocytes, LBR and CLBR.Our findings are consistent with most reports in the literature, including a recent meta-analysis .Other studies reported differentresults that endometrioma surgery diminishing ovarian reserve, leading to lower pregnancy rates in IVF [30.31]. However, these studies were conducted on limited numbers of patients, with differences surgical procedure and surgeon's expertise. Our results including CLBR per oocyte retrieval further confirmed thatwith comparable ovarian reserves, cystectomy before operationproduced similar IVF/ICSI outcomes compared with endometrioma in situ.
In comparing primary and recurrent endometriomas, our results showedweaker ovarian responses to COS in the recurrent endometrioma group. This finding is inconsistent with a previous study, whichreported patients with recurrent endometriomas have the same ovarian response . Incontrast, the outcomes of IVF/ICSI including LBR and CLBR in our study were compatible between these two groups, and was consistent with this study .There were study histologically confirmed surgery for recurrent endometrioma is associated with greater loss of ovarian tissue, which is more harmful to ovarian reserve compared with endometriomas operated for the first time . Park et al., also reported that second-line surgery for recurrent endometrioma have deleterious effects on IVF outcomes, including ovarian response, and CPR compared with in situ recurrent endometrioma . It wasalso reported that spontaneous cumulative pregnancy rate is almost half after second-line surgery for endometrioma comparing with those obtained after primary surgery . Therefore, a conservative management for recurrent endometrioma is more suitable for women with fertility desire.
Our study showed presence of endometrioma was associated withfewer blastocyst formations, compared with the endometriosis or control group.Such effects seemed to disappear after cystectomy of endometrioma. The poorer ovarian response and lower blastocyst formation rate wereunlikely consequences of deleterious effects of surgery on the endometriomas, but more likely due to endometrioma per se. There are growing studies showed ovarian quality may be deteriorated by endometrioma . One recent study using scRNA-seq compared oocytes from patients with endometrioma and healthy oocytes revealed a differential transcriptomic profile indicating lower oocyte quality in endometrioma . These mechanisms may explain how blastocyst formation rate we found was lower in the endometrioma group.
Our study has some strengths. First, our primary outcome is CLBR per oocyte retrieval which was seldom mentioned in previous studies, and was a better indicator of quality and success in IVF/ICSI, as cryopreservation is an integral part of IVF . Second, all our patients had undergone ovarian stimulation and IVF performed at a single medical center. In this regard, all measurements (AMH and TVUS) were performed consistently. Third, we had compared presence of endometrioma with endometriosis. This issue is not commonly addressed, but has practical implications. Our results showed for the first time, that the presence of endometrioma negatively influenced ovarian responsiveness and blastocyst formation rate. The main limitation of this work is its retrospective design nature. In addition, the endometriosis group is heterogeneous, including patients with peritoneal endometriosis or DIE, and some of them have no pathological diagnosis. Nevertheless, it is nowadays well accepted that the TVUS is a highly accurate and reproducible method for non-invasive diagnosis of DIE and ovarian lesions . Another limitation is that we did not stratified patients according to their endometriosis stages, and only stratified those with endometrioma or endometriosis. As increasing number of patients are receiving conservative treatment before IVF/ICSI, the presence or absence of endometrioma is a more useful characteristic in daily practice.
In conclusion,we showed the IVF/ICSI outcomesare comparable in those with endometriomaand in controls. Although blastocyst formation rate was lower and gonadotropin consumption was higher in thosewith endometrioma, IVF/ICSI outcomes of patients with endometriomawere no worse than those with endometriosis. Cystectomy for endometrioma did not alter the IVF/ICSI outcomes if the ovarian reserve was comparable. Recurrent endometrioma did notshow worse impacts on the IVF/ICSI outcomecompared with primary endometrioma.