Impact of stage III-IV endometriosis on recipients of sibling oocytes: matched case-control study

What is the impact of endometriosis and the AFS stage on cumulative pregnancy rates in IVF programs?

BACKGROUND

Endometriosis is commonly observed in infertile women and can be staged with regard to severity [e.g. according to the American Fertility Society (AFS) classification]. This condition can cause infertility through impaired oocyte quality, fertilization disorders, tubal lesions, adhesions, deep infiltration, and adenomyosis. Although women with endometriosis often turn to in vitro fertilization (IVF) programs, the literature data on IVF outcomes are sometimes contradictory (i.e. the same as in other etiologies of infertility, or worse). The objective of the present study was to assess and compare pregnancy rates in women with and without endometriosis and according to the endometriosis stage.

METHODS

We retrospectively studied clinical and ongoing pregnancy rates in IVF and the cumulative pregnancy rates after frozen/thawed embryo transfers, in women without endometriosis (group A) or with endometriosis (group B). We further compared groups in which endometriosis was staged according to the revised AFS classification: stage 1/2 (group C), stage 3/4 (group D, without endometrioma), and endometrioma alone (group E).

RESULTS

We documented 430 cycles in group A and 460 in group B (including 56 in group C, 88 in group D and 316 in group E). After fresh or frozen/thawed embryo transfers, the differences in ongoing pregnancy rates between groups A and B were not significant. However the cumulative rates per couple were significantly lower (p < 0.05) in group D.

CONCLUSIONS

We recommend IVF for women with endometriosis because the pregnancy rates are similar to those observed for women with other types of infertility. This approach is in line with the international guidelines issued by assisted reproductive technology societies. These results again raise the question of whether surgical resection of deep infiltrating endometriosis (stage 3/4) should be recommended before admission to an IVF program. Trial registration This study was approved by an institutional review board (CPP Ouest VI, Brest, France): reference: B2020CE.43.

Live Birth After Oocyte Donation In Vitro Fertilization Cycles in Women With Endometriosis: A Systematic Review and Meta-Analysis

Importance

Although multiple mechanisms have been proposed to explain the infertility related to endometriosis, there are no conclusive data on the association of endometriosis with endometrial receptivity. The oocyte donation model in assisted reproduction technology (ART) cycles can clarify this issue.

Objective

To explore the association of a history of endometriosis with ART outcomes in recipients of oocyte donation.

Data Sources

In this systematic review and meta-analysis, electronic databases were searched from inception until August 31, 2023, using combinations of relevant keywords. Moreover, we retrieved data from the databases of the Society for Assisted Reproductive Technology (SART) in the US and the Human Fertilization and Embryology Authority (HFEA) in the United Kingdom.

Study Selection

Observational studies were included if they investigated the impact of endometriosis on ART outcomes with donor oocytes.

Data Extraction and Synthesis

Publicly available data related to ART from various sources were gathered, and a retrospective aggregate and nonaggregate analysis using registries of in vitro fertilization cycles with oocyte or embryo donation was conducted.

Main Outcomes and Measures

The primary outcome was live birth rate (LBR) following oocyte donor cycles. The effect measures of comparisons between groups are presented as odds ratios (ORs) with a 95% CI.

Results

This study analyzed 7212 oocyte donation cycles from 4 studies for the meta-analysis, along with 162 082 cycles from 2 registries (137 182 from SART and 24 900 from HFEA). No significant differences between the groups were observed in the meta-analysis of published data after adjusting for confounding factors (OR, 0.54; 95% CI, 0.19-1.57). A statistically significant lower LBR was identified in women with endometriosis when analyzing the aggregate data from SART and HFEA databases (OR, 0.89; 95% CI, 0.81-0.97).

Conclusions and Relevance

This study found a modest decrease in LBR among women with a history of endometriosis, although only results from the pooled analysis of registry data and not those from the meta-analysis reached statistical significance. These findings suggest that a marginal impairment of uterine receptivity may contribute to infertility mechanisms in women affected by endometriosis.

Is endometrial receptivity affected in women with endometriosis? Results from a matched pair case-control study of assisted reproductive technology treatments

RESEARCH QUESTION

Is endometriosis detrimental to embryo implantation?

DESIGN

A retrospective matched case-control study of women with a surgical or ultrasound diagnosis of endometriosis at Fondazione IRCCS Ca'Granda Ospedale Maggiore Policlinico di Milano between 2015 and 2021. Women with endometriosis who underwent a 'freeze-all' cycle during an IVF treatment were eligible to be included. They were matched to patients without the disease, who also underwent cryopreserved blastocyst transfer cycles, in a 1:1 ratio by age (±1 year), and number (=) and quality (±1 top versus low) of cryopreserved blastocysts. All women underwent single frozen embryo transfer, and assisted reproductive technology outcomes suggested by the Core Outcome Measure for Infertility Trials initiative were evaluated. The main outcome was the cumulative live birth rate per cycle.

RESULTS

One hundred and one women with endometriosis and 101 matched unaffected women were included. Cumulative live birth rate per cycle did not vary between women with and without endometriosis (50% versus 58%, respectively; P = 0.32). On the basis of the Kaplan-Meier analysis, the predicted success rates over four embryos transferred were also similar (74% versus 82%, respectively; P = 0.67).

CONCLUSION

In women with moderate or severe endometriosis, these retrospective results seem to indicate no or a limited effect of the disease on endometrial receptivity.

Oocyte donation outcomes in endometriosis patients with multiple IVF failures

RESEARCH QUESTION

What are the reproductive outcomes and the prognostic factors of live birth rates in patients with endometriosis referred to oocyte donation after multiple IVF failures?

DESIGN

Observational cohort study including all women with endometriosis-related infertility and two or more failed IVF/intracytoplasmic sperm injection (ICSI) cycles referred to oocyte donation between January 2013 and June 2022. Endometriosis was diagnosed based on published imaging criteria, and was confirmed histologically in women who had a history of surgery for endometriosis. The main outcome measured was the cumulative live birth rate (CLBR). The characteristics of women who had a live birth were compared with those who did not using univariate and multivariate analysis to identify determinant factors of fertility outcome.

RESULTS

Fifty-seven patients underwent 90 oocyte donation cycles after 244 failed autologous IVF cycles. The mean ± SD age of the population was 36.8 ± 3.3 years, with a mean duration of infertility of 3.6 ± 2.2 years, and a mean number of autologous IVF/ICSI cycles of 4.4 ± 2.3 cycles per patient. Three patients (5.3%) had superficial peritoneal endometriosis, two patients (3.5%) had ovarian endometriomas, and 52 patients (91.2%) had deep infiltrating endometriosis, among which 30 patients (57.7%) had bowel lesions. Thirty patients (52.6%) had associated adenomyosis. Overall, CLBR per patient was 36/57 (63.2%). After multivariate analysis, only being nulligravida (P=0.002) remained an independent negative predictive factor of the live birth rate. Previous surgery did not impact reproductive outcomes.

CONCLUSION

This study suggests that oocyte donation appears to be a viable option to optimize the live birth rate in women with endometriosis-related infertility and recurrent IVF failures.

Endometriosis, Oocyte, and Embryo Quality

Endometriosis is a common finding among women with infertility, and women who are diagnosed with endometriosis are almost twice as likely to experience infertility. Mechanisms by which endometriosis causes infertility remain poorly understood. In this review, we evaluate the current literature on the impact of endometriosis on oocyte and embryo quality. The presence of endometriosis evidently reduces ovarian reserve, oocyte quality, and embryo quality; however, this does not appear to translate to a clear clinical impact. Analysis of data from large assisted reproduction technology registries has shown that women with endometriosis have a lower oocyte yield but no reduction in reproductive outcomes. There is a need for future studies in the form of well-designed randomized controlled trials to further evaluate the role of surgical and medical treatment options in women with endometriosis undergoing assisted conception.

Impact of endometriosis on embryo quality and endometrial receptivity in women undergoing assisted reproductive technology

ART is an important treatment method for infertile patients with endometriosis. However, the effects of endometriosis on embryo quality and endometrial receptivity remain unclear. Thus, we aimed to simultaneously investigate the impact of endometriosis and its stage on embryo quality and endometrial receptivity in women undergoing ART. We retrospectively analyzed the data from patients with and without endometriosis who underwent oocyte retrieval and/or high-quality embryos transfer between July 2015 and December 2020, including 1312 IVF cycles and 608 IVF or frozen-thawed embryo transfer (FET) cycles, respectively. The endometriosis group had a lower percentage of good cleavage-stage embryos and fertilization rates than those in the control group (p = 0.038 and 0.008, respectively). The number of retrieved oocytes, MII oocytes, cleavage, blastocysts, and blastulation rates was comparable between two groups. We found no significant difference in clinical pregnancy, implantation, live birth, miscarriage, or multiple pregnancy rates between the two groups among patients who transferred high-quality embryos. Stratification analysis showed that patients with stage III-IV endometriosis had fewer retrieved oocytes than those with stage I-II endometriosis (p = 0.012) and marginally fewer retrieved oocytes than the control group (p = 0.051). The stage I-II group had the lowest percentage of good cleavage-stage embryos, which was significantly lower than that of the control group (p = 0.043). In FET cycles, patients with stage III-IV endometriosis had a higher miscarriage rate than those in the control group (p = 0.023). Our results suggest that endometriosis does not alter endometrial receptivity but affects embryo quality, oocyte fertilization ability, and ovarian response.

Endometriosis-associated infertility: From pathophysiology to tailored treatment

Despite the clinically recognized association between endometriosis and infertility, the mechanisms implicated in endometriosis-associated infertility are not fully understood. Endometriosis is a multifactorial and systemic disease that has pleiotropic direct and indirect effects on reproduction. A complex interaction between endometriosis subtype, pain, inflammation, altered pelvic anatomy, adhesions, disrupted ovarian reserve/function, and compromised endometrial receptivity as well as systemic effects of the disease define endometriosis-associated infertility. The population of infertile women with endometriosis is heterogeneous, and diverse patients' phenotypes can be observed in the clinical setting, thus making difficult to establish a precise diagnosis and a single mechanism of endometriosis related infertility. Moreover, clinical management of infertility associated with endometriosis can be challenging due to this heterogeneity. Innovative non-invasive diagnostic tools are on the horizon that may allow us to target the specific dysfunctional alteration in the reproduction process. Currently the treatment should be individualized according to the clinical situation and to the suspected level of impairment. Here we review the etiology of endometriosis related infertility as well as current treatment options, including the roles of surgery and assisted reproductive technologies.

Endometriosis and oocyte quality: an analysis of 13 614 donor oocyte recipient and autologous IVF cycles

STUDY QUESTION

Does endometriosis affect live birth following donor oocyte recipient versus autologous IVF?

SUMMARY ANSWER

There was no significant difference in the live birth rate (LBR) in women with endometriosis undergoing donor oocyte recipient cycles versus autologous IVF cycles.

WHAT IS KNOWN ALREADY

For infertile women with endometriosis, IVF is often considered as a treatment option. Lower implantation and pregnancy rates have been observed following IVF in women with endometriosis. It has been debated whether the lower pregnancy rate is due to the effect on oocyte quality or the endometrium, thus affecting implantation. To delineate whether endometriosis affects oocyte quality or the endometrium, we planned a study, using a donor oocyte recipient model, where the recipients were women diagnosed with endometriosis and compared their outcomes with women who underwent autologous IVF, who had also been diagnosed with endometriosis.

STUDY DESIGN, SIZE, DURATION

Human Fertilization and Embryology Authority (HFEA) anonymized data from 1996 to 2016 were analyzed. This comprised of a total of 758 donor oocyte recipients, where the recipients were women diagnosed with endometriosis, and 12 856 autologous IVF cycles where the women were diagnosed with endometriosis as the sole cause of infertility.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Data on all women with endometriosis undergoing donor oocyte recipient and autologous IVF cycles were analyzed to compare live birth outcomes. Logistic regression analysis was performed adjusting for number of previous IVF cycles, previous live birth, period of treatment, day of embryo transfer, number of embryos transferred and fresh or frozen embryo transfer cycle.

MAIN RESULTS AND THE ROLE OF CHANCE

There was no significant difference in the LBR in women with endometriosis undergoing donor oocyte recipient fresh embryo transfer cycles compared to women undergoing autologous IVF fresh embryo transfer cycles (31.6% vs 31.0%; odds ratio (OR) 1.03, 99.5% CI 0.79–1.35). After adjusting for confounders, there was no significant difference in LBR in women with endometriosis undergoing donor oocyte recipient fresh embryo transfer cycles versus autologous fresh embryo transfer cycles (adjusted OR (aOR) 1.05, 99.5% CI 0.79–1.41).

There was no significant difference in the LBR in women with endometriosis undergoing donor oocyte recipient frozen embryo transfer cycles compared to women undergoing autologous frozen embryo transfer cycles (19.6% vs 24.0%; OR 0.77, 99.5% CI 0.47–1.25). After adjusting for potential confounders, there was no significant difference in the LBR in women undergoing donor oocyte recipient frozen embryo transfer cycles compared with autologous frozen embryo transfer cycles (aOR 0.85, 99.5% CI 0.51–1.41).

LIMITATIONS, REASONS FOR CAUTION

Although the analysis was adjusted for potential confounders, there was no information on the extent and classification of endometriosis as well as oocyte number. Furthermore, adenomyosis is thought to co-exist in women with endometriosis and may have independent pathophysiological mechanisms affecting fertility, for which there was no information.

WIDER IMPLICATIONS OF THE FINDINGS

The study shows no difference in LBR between donor oocyte recipient cycles in which all recipients had endometriosis compared to autologous IVF cycles in women with endometriosis. Therefore, this study finding suggests that there may be a minimal or no effect of oocyte quality on IVF outcomes in women with endometriosis.

STUDY FUNDING/COMPETING INTEREST(S)

No funding was obtained. M.S.K. is an associate editor with Human Reproduction Open. He was not involved in the editorial or peer review process for the manuscript.

TRIAL REGISTRATION NUMBER

N/A.

Assessment of TET1 gene expression, DNA methylation and H3K27me3 level of its promoter region in eutopic endometrium of women with endometriosis and infertility

Endometriosis is the cause of infertility. The eutopic endometrium of women with endometriosis showed an aberrant expression pattern of multitude genes. The role of TET1 protein in the pathogenesis of endometriosis and related infertility is not sufficiently known. Further, knowledge on TET1 transcriptional control still remains incomplete. The aim of the study was assessment of TET1 gene expression, DNA methylation and H3K27me3 level of its promoter region in eutopic endometrium of women with endometriosis and infertility. The study included 44 infertile patients with endometriosis (IWE) and 77 infertile (IW) and fertile (FW) patients without endometriosis. The research material was eutopic endometrium. The TET1 mRNA level was analyzed by qPCR. Western blot was used to evaluate the level of TET1 protein. The level of DNA methylation and H3K27me3 level of TET1 gene's promoter region were assessed using HRM and ChIP qPCR, respectively. The level of TET1 expression (TET1 mRNA; TET1 protein level) was lower in IWE during the implantation window (p < 0.001; p = 0.0329). The level of TET1 DNA methylation was higher in the secretory endometrium in mild and advanced IWE (p < 0.004; p < 0.008). H3K27me3 level did not differ between the study groups. The diminished expression of TET1 gene during the secretory phase, may account for the aberrant process of embryonic implantation in infertile endometriosis patients. DNA hypermethylation of TET1 gene is a potential relevant regulator of its expression. H3K27me3 occupancy does not affect the expression of TET1 gene in our study group.

Does current ovarian endometrioma increase the time for DOR patients to reach live birth in IVF?

Background

The contents of ovarian endometrioma (OMA) such as inflammatory mediators, reactive oxygen species, and iron may disrupt normal folliculogenesis and result in subsequent oocyte apoptosis. Therefore, women with OMA have a potential risk of diminished ovarian reserve (DOR). The purpose of this study is to compare the in vitro fertilization (IVF) outcomes and efficiency between DOR patients with and without current OMA.

Methods

This retrospective case-control study included a total of 493 women with DOR (serum anti-Müllerian hormone level < 1.1 ng/mL). Ninety patients with OMA (Group A) underwent 191 IVF cycles and 403 patients without ovarian OMA (Group B) underwent 888 IVF cycles in our center between January 2014 and December 2018. Basal characteristics and IVF outcomes were compared between Group A and Group B. Time to achieve live birth were compared between patients with live birth in two groups (Group A1, 31 patients; Group B1, 132 patients).

Results

Clinical and demographic characteristics of patients were similar respectively between groups (A vs. B, A1 vs. B1). There were no statistically significant differences in implantation rate, live birth rate per OPU and per ET cycle and the cumulative live birth rate per patient and per patient with good-quality embryos between Group A and Group B (P > 0.05). Total time to achieve live birth has no statistically significant difference between Group A1 and Group B1 (P > 0.05).

Conclusion

For DOR women, presence of endometrioma did not affect the IVF outcomes. Even the time to get live birth was not prolonged by current OMA.

Epigenetic Factors in Eutopic Endometrium in Women with Endometriosis and Infertility

Eutopic endometrium in patients with endometriosis is characterized by aberrant expression of essential genes during the implantation window. It predisposes to disturbance of endometrial receptivity. The pathomechanism of implantation failures in women with endometriosis remains unclear. This paper aims to summarize the knowledge on epigenetic mechanisms in eutopic endometrium in the group of patients with both endometriosis and infertility. The impaired DNA methylation patterns of gene promoter regions in eutopic tissue was established. The global profile of histone acetylation and methylation and the analysis of selected histone modifications showed significant differences in the endometrium of women with endometriosis. Aberrant expression of the proposed candidate genes may promote an unfavorable embryonic implantation environment of the endometrium due to an immunological dysfunction, inflammatory reaction, and apoptotic response in women with endometriosis. The role of the newly discovered proteins regulating gene expression, i.e., TET proteins, in endometrial pathology is not yet completely known. The cells of the eutopic endometrium in women with endometriosis contain a stable, impaired methylation pattern and a histone code. Medication targeting critical genes responsible for the aberrant gene expression pattern in eutopic endometrium may help treat infertility in women with endometriosis.

The impact of endometriosis on embryo morphokinetics: embryos from endometriosis patients exhibit delayed cell cycle milestones and decreased blastulation rates

PURPOSE

To compare morphokinetic parameters in embryos obtained from women with and without endometriosis.

METHODS

We evaluated a total of 3471 embryos resulting from 434 oocyte retrievals performed at a single academic center. One thousand seventy-eight embryos were obtained from women affected by endometriosis and 2393 came from unaffected controls. All embryos were cultured in a time-lapse incubator chamber for up to 6 days. IVF cycle outcomes and morphokinetic parameters collected prospectively were retrospectively reviewed.

RESULTS

Morphokinetic data suggest that embryo development is impaired in embryos obtained from women with endometriosis (EE). EE were slower to achieve the 2-8 cell stages compared to control embryos (CE) (p < 0.001); additionally, time to compaction was delayed compared to CE (p = 0.015). The timing of late developmental events, including morulation and blastulation was also delayed in the endometriosis cohort (p < 0.001). In addition to demonstrating delayed cell cycle milestones, EE were less likely than controls to progress to morula, blastocyst, and expanded blastocyst stages (p < 0.001). Furthermore, a smaller proportion of embryos in the endometriosis group fell into optimal kinetic ranges for cc2 (p = 0.003), t5 (p = 0.019), tSB (p < 0.001), and tEB (p = 0.007). There were no significant differences in clinical pregnancy or live birth rates between groups.

CONCLUSION

Embryos from endometriosis patients demonstrate impairments in both early and late developmental events, and progress to the morula, blastocyst, and expanded blastocyst stages at lower rates than control embryos. Despite these differences, IVF outcomes are similar for patients with and without endometriosis.

Novel therapeutic targets to improve IVF outcomes in endometriosis patients: a review and future prospects

BACKGROUND

Patients with endometriosis often experience infertility and have poor IVF outcomes, with low fertilization and pregnancy rates. Although many theories have tried to explain the mechanisms underlying infertility in these patients, none of them is conclusive.

OBJECTIVE AND RATIONALE

In this review, we discuss the pathologic mechanisms through which endometriosis likely leads to infertility along with the therapeutic options used to date to treat endometriosis-related infertility and, thereby, to improve IVF outcomes in patients with endometriosis.

SEARCH METHODS

We performed a comprehensive literature search of clinical outcomes in endometriosis and the molecular mechanisms contributing to oocyte quality using the PubMed database to identify human and animal studies published from 1992 until September 2020. In total, 123 manuscripts were included.

OUTCOMES

While some theories propose that endometriosis patients may have fertility problems as a result of decreased endometrial receptivity, others reinforce the idea that infertility could be associated with oocyte alterations and lower implantation rates. Single-cell RNA sequencing of oocytes from patients with endometriosis has identified dysregulated mechanisms involved in steroid metabolism and biosynthesis, response to oxidative stress and cell cycle regulation. Dysregulation of these mechanisms could result in the poor IVF outcomes observed in patients with endometriosis. Further, impaired steroidogenesis may directly affect oocyte and embryo quality. Increased oxidative stress in patients with endometriosis also has a detrimental effect on the follicular microenvironment, inducing cell cycle dysregulation in oocytes, poor oocyte quality, and infertility. Moreover, granulosa cells in the context of endometriosis undergo increased apoptosis and have an altered cell cycle that could adversely affect folliculogenesis, oocyte and embryo quality, and IVF outcomes. Endometriosis is also associated with inflammatory damage and impaired angiogenesis, which could be directly correlated with poor IVF outcomes. While therapeutic options using GnRH analogues, progestins and aromatase inhibitors do not improve endometriosis-related infertility, anti-inflammatory agents and antioxidant supplementation could improve oocyte quality as well as implantation and clinical pregnancy rates in patients with endometriosis.

WIDER IMPLICATIONS

Endometriosis is a heterogeneous disease whose pathogenesis is complex and could affect fertility by altering a collection of molecular mechanisms in oocytes. Thus, a single model is not sufficient to describe endometriosis-related infertility. Dysregulation of steroidogenesis, oxidative stress, cell cycle progression, inflammation and angiogenesis in the follicular environment and oocytes in individuals with endometriosis are all possible contributors to endometriosis-related infertility. Therefore, treatments targeting these mechanisms could be therapeutic alternatives to improve IVF outcomes for these patients.

Endometrial Receptivity Analysis (ERA): data versus opinions

This article summarises and contextualises the accumulated basic and clinical data on the ERA test and addresses specific comments and opinions presented by the opponent as part of an invited debate. Progress in medicine depends on new technologies and concepts that translate to practice to solve long-standing problems. In a key example, combining RNA sequencing data (transcriptomics) with artificial intelligence (AI) led to a clinical revolution in personalising disease diagnosis and fostered the concept of precision medicine. The reproductive field is no exception. Translation of endometrial transcriptomics to the clinic yielded an objective definition of the limited time period during which the maternal endometrium is receptive to an embryo, known as the window of implantation (WOI). The WOI is induced by the presence of exogenous and/or endogenous progesterone (P) after proper oestradiol (E2) priming. The window lasts 30-36 hours and, depending on the patient, occurs between LH + 6 and LH + 9 in natural cycles or between P + 4 and P + 7 in hormonal replacement therapy (HRT) cycles. In approximately 30% of IVF cycles in which embryo transfer is performed blindly, the WOI is displaced and embryo-endometrial synchrony is not achieved. Extending this application of endometrial transcriptomics, the endometrial receptivity analysis (ERA) test couples next-generation sequencing (NGS) to a computational predictor to identify transcriptomic signatures for each endometrial stage: proliferative (PRO), pre-receptive (PRE), receptive (R) and post-receptive (POST). In this way, personalised embryo transfer (pET) may be possible by synchronising embryo transfer with each patient's WOI. Data are the only way to confront arguments sustained in opinions and/or misleading concepts; it is up to the reader to make their own conclusions regarding its clinical utility.

Altered transcriptome in cumulus cells of infertile women with advanced endometriosis with and without endometrioma

RESEARCH QUESTION

Is the transcriptome of cumulus cells of infertile women with advanced endometriosis (EIII/IV), with and without endometrioma, altered?

DESIGN

In this prospective case-control study, next-generation RNA sequencing was used to compare the transcript profile of cumulus cells among infertile patients undergoing ovarian stimulation for intracytoplasmic sperm injection with EIII/IV, with (n = 9) and without endometrioma (n = 9), and controls (n = 9). An in-silico enrichment analysis was conducted to establish the possibly altered pathways in cumulus cells of patients with endometriosis.

RESULTS

Most of the differentially expressed genes (DEG) were found when cumulus cells from women with EIII/IV with endometrioma were compared with controls (DEG, n = 461). In women with EIII/IV without endometrioma, only 66 DEG were verified compared with controls. The enrichment analysis showed that some DEG in cumulus cells of endometriosis are involved in important pathways for the oocyte competence acquisition, such as oxidative phosphorylation, metabolism, mitochondrial function, acetylation and steroid biosynthesis. No DEG were found when cumulus cells from women with EIII/IV with and without endometrioma were compared.

CONCLUSION

RNA sequencing results suggest that cumulus cells of infertile women with EIII/IV have an altered transcriptome, regardless of endometrioma. The present findings offer a better understanding of the genes and molecular mechanisms that may be involved in endometriosis-related infertility, mostly in the oocyte competence acquisition process.

Early Pregnancy Outcomes in Fresh Versus Deferred Embryo Transfer Cycles for Endometriosis-Associated Infertility: A Retrospective Cohort Study

Given the estrogen-dependence associated with endometriosis, hyper-stimulation associated with assisted reproduction treatment may exacerbate the disease process and adversely affect endometrial receptivity and subsequent implantation. In this way, a freeze-all deferred embryo transfer (ET) approach may benefit patients with endometriosis, although controversy exists regarding the mechanism of endometriosis-associated infertility and benefits of deferred ET on endometrial receptivity. Hence, the purpose of this study was to compare in vitro fertilization (IVF) outcomes in women with endometriosis, diagnosed by histology, undergoing fresh versus deferred-ET after elective cryopreservation. Of the 728 women included, no significant differences were observed in baseline patient characteristics and response to gonadotrophin stimulation between fresh and deferred ET groups. Furthermore, no significant differences in implantation rate (49.7 vs. 49.9%, p = 0.73), clinical pregnancy rate (40.9 vs. 39.9%, p = 0.49), and miscarriage rate (9.4 vs. 9.9%, p = 0.63) were observed between fresh and deferred ET groups, respectively. Hence, contrary to previous studies, our results suggest that a deferred ET “freeze-all” IVF strategy does not improve early pregnancy outcomes among women with endometriosis. However, prospective studies are required to validate these findings and further insight into the etiology and pathogenesis of endometriosis-associated infertility are necessary to optimize IVF protocols in this population.

Number needed to freeze: cumulative live birth rate after fertility preservation in women with endometriosis

RESEARCH QUESTION

How does the number of oocytes used affect the cumulative live birth rate (CLBR) in endometriosis patients who had their oocytes vitrified for fertility preservation?

DESIGN

Retrospective observational study including data from 485 women with endometriosis who underwent fertility preservation from January 2007 to July 2018. Survival curves and Kaplan-Meier plots were used to analyse the CLBR according to the number of vitrified oocytes used. Endometriosis curves were compared with plots developed using elective fertility preservation (EFP) patients as control group. Log-rank, Breslow and Tarone-Ware tests were used to compare the survival curves.

RESULTS

The CLBR increased as the number of oocytes used per patient rose, reaching 89.5% (95% confidence interval [CI] 80.0-99.1%) using 22 oocytes. Higher outcomes were observed in young women (≤35 years old versus >35 years old). In the younger group, the CLBR was 95.4% (95% CI 87.2-103.6%) using approximately 20 oocytes versus 79.6% (95% CI 58.1-101.1%) in older women (log-rank [Mantel-Cox] P = 0.002). The mean age was higher in EFP patients (37.2 ± 4.9 versus 35.7 ± 3.7; P < 0.001). The outcome was better in the endometriosis group as compared with EFP: a CLBR of 89.5% (95% CI 80.0-99.1%) versus 59.9% (95% CI 51.4-68.6%) when 22 oocytes were used (log-rank [Mantel-Cox] P < 0.00001).

CONCLUSION

The probability of live birth increases as the number of oocytes used increases in patients with endometriosis, but better outcomes were observed among young women. The information provided here may be of interest to both patients and treating physicians for counselling purposes.

Impaired implantation in endometriosis compared with couples with male subfertility after transfer of equal quality embryos: a matched cohort study

RESEARCH QUESTION

Is implantation impaired in patients with endometriosis undergoing IVF and intracytoplasmatic sperm injection (ICSI) cycles?

DESIGN

A retrospective matched cohort study was carried out on IVF/ICSI cycles with fresh single embryo transfer at the Department of Assisted Reproductive Medicine, Ghent University Hospital, Belgium, between July 2015 and August 2017 (n = 1053). A total of 118 endometriosis cases were matched 1:1 to 118 couples diagnosed with male subfertility and stratified by embryo quality (identical ALPHA grading categories), female age (±1 year) and parity (±1 delivery). Transvaginal ultrasound, magnetic resonance imaging or laparoscopy was used to diagnosed endometriosis, and the revised American Society for Reproductive Medicine score was used to classify the endometriosis into grade I/II versus grade III/IV. Male subfertility was defined in accordance with World Health Organization criteria (fifth edition).

RESULTS

Compared with endometriosis cases, control couples with male subfertility had significantly higher rates of positive HCG test on day 16 (P = 0.047, OR 2.077, CI 1.009 to 4.276), ongoing implantation (defined as a positive fetal heart rate on transvaginal ultrasound at a gestational age of at least 6.5-7 weeks) (P = 0.038, OR 2.265, CI 1.048 to 4.893), ongoing pregnancy (defined by a vital pregnancy at 11 weeks) (P = 0.046, OR 2.292, CI 1.016 to 5.173) and live birth (P = 0.043, OR 2.502, CI 1.029 to 6.087).

CONCLUSIONS

After matching for embryo quality, woman's age and parity, rates of positive HCG tests, ongoing implantation, ongoing pregnancy and live birth were more than twice as high in the control group compared with the endometriosis group.

Endometriosis Lowers the Cumulative Live Birth Rates in IVF by Decreasing the Number of Embryos but Not Their Quality

Endometriosis and infertility are closely linked, but the underlying mechanisms are still poorly understood. This study aimed to evaluate the impact of endometriosis on in vitro fertilization (IVF) parameters, especially on embryo quality and IVF outcomes. A total of 1124 cycles with intracytoplasmic sperm injection were retrospectively evaluated, including 155 cycles with endometriosis and 969 cycles without endometriosis. Women with endometriosis had significantly lower ovarian reserve markers (AMH and AFC), regardless of previous ovarian surgery. Despite receiving significantly higher doses of exogenous gonadotropins, they had significantly fewer oocytes, mature oocytes, embryos, and top-quality embryos than women in the control group. Multivariate analysis did not reveal any association between endometriosis and the proportion of top-quality embryo (OR = 0.87; 95% CI [0.66-1.12]; p = 0.3). The implantation rate and the live birth rate per cycle were comparable between the two groups (p = 0.05), but the cumulative live births rate was significantly lower in in the endometriosis group (32.1% versus 50.7%, p = 0.001), as a consequence of the lower number of frozen embryos. In conclusion, endometriosis lowers the cumulative live birth rates by decreasing the number of embryos available to transfer, but not their quality.

Single-cell RNA sequencing of oocytes from ovarian endometriosis patients reveals a differential transcriptomic profile associated with lower quality

STUDY QUESTION

Do oocytes from women with ovarian endometriosis (OE) have a different transcriptomic profile than those from healthy women?

SUMMARY ANSWER

Oocytes from endometriosis patients, independently of whether they came from the affected ovary, exhibited a differential transcriptomic profile compared to oocytes from healthy egg donors.

WHAT IS KNOWN ALREADY

Studies of endometriosis have sought to determine whether OE affects oocyte quality. While many reports indicate that oocytes recovered from endometriotic ovaries may be affected by the disease, other studies have found no significant differences among oocyte/embryo quality and fertilization, implantation and pregnancy rates in women with endometriosis.

STUDY DESIGN, SIZE, DURATION

This prospective study compared metaphase II (MII) oocytes (n = 16) from endometriosis patients (n = 7) to oocytes (n = 16) from healthy egg donors (n = 5) by single-cell RNA sequencing (scRNA-seq). Participants were recruited between December 2016 and February 2018 at IVI-RMA Valencia and Vigo clinics.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Human MII oocytes were collected from healthy egg donors and OE patients aged 18-34 years, with a body mass index of <30 and >6 pre-antral follicles. RNA was extracted, cDNA was generated and libraries were constructed and sequenced. scRNA-seq data libraries were processed and statistically analysed. Selected genes were validated by quantitative real-time PCR.

MAIN RESULTS AND THE ROLE OF CHANCE

Our scRNA-seq results revealed an effect of endometriosis on global transcriptome behaviour in oocytes from endometriotic ovaries. The highest number of differentially expressed genes (DEGs) was found when oocytes from women with OE were compared to oocytes from healthy donors [520 DEGs (394 upregulated and 126 downregulated)], independently of whether oocytes came from an affected or unaffected ovary. Among the top 20 significant DEGs in this comparison, most were upregulated, including APOE, DUSP1, G0S2, H2AFZ, ID4, MGST1 and WEE1. PXK was the only downregulated gene. Subsequently, functional analysis showed 31 enriched functions deregulated in endometriosis patients (Benjamini P < 0.1), being 16 significant enriched functions considering Benjamini P < 0.05, which involved in biological processes and molecular functions, such as steroid metabolism, response to oxidative stress and cell growth regulation. In addition, our functional analysis showed enrichment for mitochondria, which are an important cellular component in oocyte development. Other functions important in embryo development, such as angiogenesis and methylation, were also significantly enriched.

LARGE SCALE DATA

All raw sequencing data are submitted in Gene Expression Omnibus (GEO) under accession number (PRJNA514416).

LIMITATIONS, REASONS FOR CAUTION

This study was restricted only to OE and thereby other anatomical entities, such as peritoneal and deep infiltrating endometriosis, were not considered. This is a descriptive study with a limited number of samples reflecting the difficulty to recruit human oocytes, especially from women with endometriosis.

WIDER IMPLICATIONS OF THE FINDINGS

This study suggests that OE exhibits a global transcriptomic effect on oocytes of patients in OE, independently if they come from an affected or unaffected ovary and alters key biological processes and molecular functions related to steroid metabolism, response to oxidative stress and cell growth regulation, which reduce oocyte quality.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by IVI Foundation, the Spanish Ministry of Economy and Competitiveness through the Miguel Servet programme (CPII018/00002 to F.D.), the Sara Borrell Program (CD15/00057 to H.F.) and the VALi+d Programe (Generalitat Valenciana); ACIF/2016/444 to A.C.). The authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

None.

REASONS FOR ENDOMETRIOSIS-ASSOCIATED INFERTILITY

This article discusses the causes and mechanisms of the occurrence of infertility in endometriosis within the framework of versions and contraversions. The magnitude of the described problem is noted not only from a medical, but also from a socio-economic perspective. Four main factors of endometriosis-associated infertility were identified: tubal-peritoneal, ovarian, embryonic and endometrial. Given the inconsistency of scientific data, the need for further research is noted.

Challenges in uncovering non-invasive biomarkers of endometriosis

Endometriosis affects up to 10% of women of childbearing age, causing symptoms that can include chronic pelvic pain and reduced fertility. The symptoms are not specific to the disease and can be confused with other gynecological conditions or normal menstruation. Currently, the disease can be only definitively diagnosed by laparoscopy, as no clinically accepted biomarker exists. Biomarker discovery can either follow a hypothesis-driven approach selecting targets to be tested based on current knowledge of the disease, or take an unbiased high-throughput screening “omics” approach, such as transcriptomics or proteomics, to identify markers that are unique or elevated in accessible bodily fluids of patients with the disease. Numerous studies have been conducted using these approaches to try and identify endometriosis biomarkers, but variabilities in study design, cohort selection, and analysis, together with the fact that most studies were small-scale, have made independent validation of biomarker candidates difficult. Therefore, efforts are underway to standardize cohort selection, patient data, and sample collection to allow better cross-study comparisons. Large scale multi-center studies using this standardized approach are necessary to validate existing endometriosis biomarker candidates and uncover potential new markers. Given the complexity and heterogeneity of the disease, it is likely that a panel of biomarkers will be necessary to diagnose and categorize endometriosis.

Predicting the likelihood of a live birth for women with endometriosis-related infertility

OBJECTIVE

Endometriosis affects 10% of women in reproductive age and alters fertility. Its management is still debated notably the timing of surgery and ART in infertility. Several tools have been created to guide the practitioner and the couple yet many limitations persist. The objective is to create a nomogram to predict the likelihood of a live birth after surgery followed by assisted reproductive technology (ART) for patients with endometriosis-related infertility.

STUDY DESIGN

All women in a public university hospital who attempted to conceive by ART after surgery for endometriosis-related infertility from 2004 to 2016 were included. We created a model using multivariable linear regression based on a retrospective database.

RESULT

Of the 297 women included, 171 (57.6%) obtained a live birth. Age, duration of infertility, number of ICSI-IVF cycles, ovarian reserve and the revised American Fertility Society (rAFS) score were included in the nomogram. The predictive model had an area under the curve (AUC) of 0.77 (95% CI, 0.75-0.79) and was well calibrated. The external validation of the model was achieved with an AUC of 0.71 (95% CI, 0.69-0.73) and calibration was good. The staging accuracy according to AUC criteria for the nomogram compared to the currently used Endometriosis Infertility Index to predict live births were 0.77 (95% CI, 0.75-0.79) and 0.60 (95% CI: 0.57-0.63), respectively.

CONCLUSION

This simple tool appears to accurately predict the likelihood of a live birth for a patient undergoing ART after surgery for endometriosis-related infertility. It could be used to counsel patients in their choice between spontaneous versus ART conception, or oocyte donation.

The Role of Fertility Preservation in Women with Endometriosis: A Systematic Review

OBJECTIVE

To summarize the available evidence concerning fertility preservation techniques in the context of women with endometriosis.

DATA SOURCES

We searched for studies published between 1984 and 2019 on endometriosis and Assisted Reproductive Technology outcomes. We searched MEDLINE and PubMed and performed a manual search of reference lists within identified studies.

METHODS OF STUDY SELECTION

A total of 426 articles were identified, and 7 studies were eligible to be included for the systematic review. We included all published studies, excluding reviews, case reports, and animal studies.

TABULATION, INTEGRATION, AND RESULTS

Despite a significant increase in the number of studies addressing fertility preservation over the study period, we found a relative lack of evidence addressing the use of fertility preservation techniques in women with endometriosis. The studies identified included 2 case reports, 1 histological science study, and 4 retrospective cohort studies.

CONCLUSION

Women with endometriosis may benefit from fertility preservation techniques. However, there currently is a paucity of data in this population, especially when compared with other indications for fertility preservation. Although much knowledge can be translated from the oncofertility discipline, we have identified and discussed endometriosis-related changes to ovarian reserve and oocyte health that justify further well-designed research to confirm that fertility preservation outcomes are similar for women with endometriosis.

Fertility Preservation in Women With Endometriosis

Infertility affects 30% to 50% of women with endometriosis. Women with endometriosis are at risk of decreased ovarian reserve, both because of the pathophysiology of the disease and iatrogenic injury resulting from surgical intervention. Fertility preservation must occur at multiple levels, including careful selection of surgical candidates, avoidance of repeat procedures, and meticulous surgical technique. Fertility preservation with oocyte or ovarian tissue cryopreservation may be considered on an individual basis for women with endometriosis, particularly those at risk of bilateral ovarian injury, such as women with bilateral endometriomas.

Medical or surgical treatment before embryo transfer improves outcomes in women with abnormal endometrial BCL6 expression

PURPOSE

To evaluate the effect of medical or surgical treatment prior to embryo transfer in women with elevated endometrial BCL6 expression and suspected endometriosis in a prospective, cohort study design at a university-associated infertility clinic.

METHODS

All subjects had at least 1 year of unexplained infertility (UI) and each prospectively underwent endometrial biopsy and immunostaining for the oncogene BCL6, prior to embryo transfer during an assisted reproductive technology (ART) cycle. To be included, subjects had to have an abnormal BCL6 result, defined by elevated HSCORE ≥ 1.4. Women that were pre-treated with laparoscopy or medical suppression with GnRH agonist (depot leuprolide acetate; Lupron®, Abbvie, Inc., Chicago, IL) for 2 months were compared to a group that went untreated (controls). Endpoints included implantation rate (IR), clinical pregnancy rate (CPR), and live birth rate (LBR), and as well as cycle characteristics. Miscarriage rate were also compared between treatment and control group.

RESULTS

Women in each group had similar characteristics. Those treated by medical suppression and those undergoing laparoscopy for endometriosis had a significantly higher LBR, (5/10; 50%; 95%CI 23.7 to 76.3%) and (11/21; 52.4%; 95%CI 32.4 to 71.7), respectively, compared to controls (4/54; 7.4%; 95%CI 2.9 to 17.6). An absolute benefit of 44.2% (16/31; 95%CI 24.6 to 61.2) and a number need to treat of 3 for those that received treatment (medical suppression and laparoscopy), compared to no treatment. Miscarriages were significantly more common in the control group.

CONCLUSIONS

Women with suspected endometriosis and aberrant endometrial BCL6 expression have worse reproductive outcomes following embryo transfer, including a high miscarriage rate, poor IR, and low LBR and CPR compared to cycles pre-treated with medical and surgical management.

Elevated peritoneal fluid ceramides in human endometriosis-associated infertility and their effects on mouse oocyte maturation

OBJECTIVE

To characterize the peritoneal fluid (PF) sphingolipid profile in endometriosis-associated infertility (EAI), and to assess the plausible functional role(s) of ceramides in oocyte maturation potential.

DESIGN

Retrospective case-control study and in vitro mouse oocyte study.

SETTING

University-affiliated hospital and university laboratory.

SUBJECTS

Twenty-seven infertile patients diagnosed with endometriosis and 20 infertile patients who did not have endometriosis; BALB/c female mice.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

PF sphingolipid concentrations. Number of metaphase II (MII) mouse oocytes.

RESULT(S)

Liquid chromatography-tandem mass spectrometry revealed 11 significantly elevated PF sphingolipids in infertile women with severe endometriosis compared with infertile women without endometriosis (change >50%, false discovery rate ≤10%). Logistic regression analysis identified three very-long-chain ceramides potentially associated with EAI. Functional studies revealed that very-long-chain ceramides may compromise or induce murine MII oocyte maturation. The oocyte maturation effects induced by the very long-chain ceramides were triggered by alterations in mitochondrial superoxide production in a concentration-dependent manner. Scavenging of mitochondrial superoxide reversed the maturation effects of C_24:0 ceramide.

CONCLUSION(S)

EAI is associated with accumulation of PF very-long-chain ceramides. Mouse studies demonstrated how ceramides affect MII oocyte maturation, mediating through mitochondrial superoxide. These results provide an opportunity for direct functional readout of pathophysiology in EAI, and future therapies targeted at this sphingolipid metabolism may be harnessed for improved oocyte maturation.

Could surgical management improve the IVF outcomes in infertile women with endometrioma?: a review

Endometriosis is a chronic inflammatory condition that affects fertility and could be toxic to the ovary. Endometrioma per se and surgical interventions for endometrioma significantly reduce the ovarian reserve. Therefore, to prepare for surgical intervention for endometrioma, the high-risk group with decreased ovarian reserve must be considered. There is no evidence to support the use of surgical intervention before in vitro fertilization (IVF) to improve the reproductive outcomes of subsequent IVF in infertile women with advanced-stage endometriosis or endometrioma. As surgical treatment has few benefits, IVF could be recommended immediately for aiding conception in these women. However, the reproductive prognosis of IVF may be worse in the more advanced stages of endometriosis. When dysmenorrhea is severe or when cancer is suspected, surgery prior to IVF may be necessary and justified. When the size of the endometrioma is very large, surgery could be required prior to IVF to facilitate access to follicles during oocyte retrieval or to improve the ovarian response to controlled ovarian stimulation. Prolonged pituitary downregulation in women with surgically diagnosed endometriosis may be helpful to increase the clinical pregnancy rate in subsequent IVF cycles. The purpose of this paper was to review the efficiency and clinical application of the surgical intervention and IVF for infertile women with advanced-stage endometriosis or endometrioma.

Chronic Niche Inflammation in Endometriosis-Associated Infertility: Current Understanding and Future Therapeutic Strategies

Endometriosis is an estrogen-dependent inflammatory disease that affects up to 10% of women of reproductive age and accounts for up to 50% of female infertility cases. It has been highly associated with poorer outcomes of assisted reproductive technology (ART), including decreased oocyte retrieval, lower implantation, and pregnancy rates. A better understanding of the pathogenesis of endometriosis-associated infertility is crucial for improving infertility treatment outcomes. Current theories regarding how endometriosis reduces fertility include anatomical distortion, ovulatory dysfunction, and niche inflammation-associated peritoneal or implantation defects. This review will survey the latest evidence on the role of inflammatory niche in the peritoneal cavity, ovaries, and uterus of endometriosis patients. Nonhormone treatment strategies that target these inflammation processes are also included. Furthermore, mesenchymal stem cell-based therapies are highlighted for potential endometriosis treatment because of their immunomodulatory effects and tropism toward inflamed lesion foci. Potential applications of stem cell therapy in treatment of endometriosis-associated infertility in particular for safety and efficacy are discussed.

Endometriosis

Endometriosis is a common inflammatory disease characterized by the presence of tissue outside the uterus that resembles endometrium, mainly on pelvic organs and tissues. It affects ~5-10% of women in their reproductive years - translating to 176 million women worldwide - and is associated with pelvic pain and infertility. Diagnosis is reliably established only through surgical visualization with histological verification, although ovarian endometrioma and deep nodular forms of disease can be detected through ultrasonography and MRI. Retrograde menstruation is regarded as an important origin of the endometrial deposits, but other factors are involved, including a favourable endocrine and metabolic environment, epithelial-mesenchymal transition and altered immunity and inflammatory responses in genetically susceptible women. Current treatments are dictated by the primary indication (infertility or pelvic pain) and are limited to surgery and hormonal treatments and analgesics with many adverse effects that rarely provide long-term relief. Endometriosis substantially affects the quality of life of women and their families and imposes costs on society similar to those of other chronic conditions such as type 2 diabetes mellitus, Crohn's disease and rheumatoid arthritis. Future research must focus on understanding the pathogenesis, identifying disease subtypes, developing non-invasive diagnostic methods and targeting non-hormonal treatments that are acceptable to women who wish to conceive.

Implications of immune dysfunction on endometriosis associated infertility

Endometriosis is a complex, inflammatory disease that affects 6-10% of reproductive-aged women. Almost half of the women with endometriosis experience infertility. Despite the excessive prevalence, the pathogenesis of endometriosis and its associated infertility is unknown and a cure is not available. While many theories have been suggested to link endometriosis and infertility, a consensus among investigators has not emerged. In this extensive review of the literature as well as research from our laboratory, we provide potential insights into the role of immune dysfunction in endometriosis associated infertility. We discuss the implication of the peritoneal inflammatory microenvironment on various factors that contribute to infertility such as hormonal imbalance, oxidative stress and how these could further lead to poor oocyte, sperm and embryo quality, impaired receptivity of the endometrium and implantation failure.

Endometrial BCL6 testing for the prediction of in vitro fertilization outcomes: a cohort study

OBJECTIVE

To evaluate endometrial BCL6 expression as a prognostic biomarker for IVF outcome in women with unexplained infertility (UI) before ET.

DESIGN

Prospective cohort study.

SETTING

University-associated infertility clinic.

PATIENT(S)

Women with UI for >1 year.

INTERVENTION(S)

We studied women with UI who underwent testing for endometrial BCL6, in an LH-timed midluteal phase biopsy and completed an IVF cycle and ET.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy rate (PR) and live birth rate per transfer was compared for women positive or negative for BCL6 expression. An abnormal BCL6 result was defined by an histologic score (>1.4).

RESULT(S)

Women with normal and abnormal BCL6 and those who conceived or not had similar characteristics. Women with low levels of BCL6 expression had a significantly higher clinical PR (11/17; 64.7%; 95% confidence interval [CI] 41.3-82.6) compared with women with abnormal (high) BCL6 expression (9/52; 17.3%; 95% CI 9.3-30.8). These results yield a relative risk of 0.267 (95% CI 0.13-0.53; P=.0004) for those with normal BCL6 expression, an absolute benefit of 47.4% (95% CI 22.5-72.0). Live birth rate was also significantly higher in women with low BCL6 expression (10/17; 58.8%; 95% CI 36.0-78.4) compared with women with abnormal BCL6 expression (6/52; 11.5%; 95% CI 5.4-23.0). The relative risk was 0.19 (95% CI 0.08-0.45; P=.0002), yielding an absolute benefit of 47.3% (95% CI 21.8-67.8).

CONCLUSION(S)

Aberrant BCL6 expression (histologic score, >1.4) was strongly associated with poor reproductive outcomes in IVF cycles in women with UI.

[IVF and endometriosis, oocyte donation and fertility preservation]

Endometriosis is a common condition, causing pain and infertility. In infertile woman with superficial peritoneal endometriosis and patent tubes, laparoscopy is recommended, followed by ovarian stimulation alone or in combination with intrauterine inseminations. In case of ovarian or deep endometriosis, the indications of surgery and assisted reproductive technologies remain to be defined precisely. In vitro fertilization is generally proposed after the failure of up to three inseminations, directly for ovarian or deep endometriosis, or in case of an associated factor of infertility, mainly male. Before ovarian stimulation in view to in vitro fertilization, a pretreatment by GnRH agonist for 2 to 6 months or combined contraceptive for 6 to 8 weeks would improve the pregnancy rate. Egg donation is effective in patients with advanced ovarian failure or lack of ovarian response to stimulation. Fertility preservation, especially by oocytes vitrified, must be proposed preventively to women with endometriosis at risk of ovarian failure, without close wish to be pregnant.

Pregnancy outcomes after controlled ovarian hyperstimulation in women with endometriosis-associated infertility: GnRH-agonist versus GnRH-antagonist

BACKGROUND OR OBJECTIVE

Endometriosis is common in women referred for infertility. In vitro fertilization provides good results but the choice of the best-controlled ovarian hyperstimulation protocol remains a subject of debate. The objective of this retrospective study was to compare pregnancy outcomes in women with endometriosis-associated infertility after COH with a long agonist protocol or a six-week oral contraception-antagonist protocol.

MATERIAL AND METHODS

Retrospective analysis of a prospective database identified 284 COH cycles - 165 with GnRH-agonist protocol (GnRH-agonist group) and 119 with GnRH-antagonist protocol (GnRH-antagonist group) - in 218 women, with endometriosis from January 2013 to October 2015.

RESULTS

No difference in the epidemiological characteristics was found between the groups. Per started cycle, pregnancy and live-birth rates after fresh embryo transfer were higher with the GnRH-agonist protocol (25% vs. 13%, P=0.02 and 18% vs. 8%, P=0.04, respectively). Considering analysis per cycle with embryo transfer, the pregnancy rate was similar in both groups while the live-birth rate was higher in the GnRH-agonist group (29% vs. 17%, P=0.053 and 22% vs. 10%, P=0.02, respectively). No difference was observed between the groups with freeze-thaw embryo transfer. Subgroup analysis (endometrioma alone, deep infiltrating endometriosis with and without endometrioma, endometriosis with and without adenomyosis) revealed no difference between the groups for either pregnancy or live-birth rates.

CONCLUSION

A GnRH-agonist protocol appears to result in higher pregnancy and live-birth rates after fresh embryo transfer in women with endometriosis-associated infertility, suggesting that a GnRH-antagonist protocol might negatively impact endometrial receptivity.

Use of medroxyprogesterone acetate in women with ovarian endometriosis undergoing controlled ovarian hyperstimulation for in vitro fertilization

This study investigated the use of medroxyprogesterone acetate (MPA) or a short protocol for controlled ovarian hyperstimulation (COH) in patients with advanced endometriosis who have normal ovarian function, and to compare cycle characteristics and pregnancy outcomes after frozen-thawed embryo transfer (FET). This was a retrospective case-control study of 244 patients with advanced endometriosis undering COH. The patients were allocated to three groups: the surgery group with MPA COH (62 patients, 71 IVF/ICSI cycles, 78 FET cycles); the aspiration group with MPA COH (85 patients had ovarian “chocolate” cysts (>3 cm) aspirated, 90 IVF/ICSI cycles, 76 FET cycles); and the short protocol group (97 patients, 101 IVF/ICSI cycles, 51 FET cycles). The results showed that higher rates of mature oocyte, D3 high quality embryo, hMG dose were observed in the two study groups using MPA compared with the short protocol. The number of >10–14 mm follicles on the trigger day, D3 top-quality embryos, viable embryos, rates of cancellation, fertilization, implantation, pregnancy outcomes were similar among the three groups. The oocytes, embryos, and pregnancy outcomes were not influenced by endometrioma surgery or presence of endometrioma. MPA COH could be effective for women with ovarian advanced endometriosis who had normal ovarian function.

Is the oocyte quality affected by endometriosis? A review of the literature

Endometriosis is an estrogen-dependent chronic inflammatory condition that affects women in their reproductive period causing infertility and pelvic pain. The disease, especially at the ovarian site has been shown to have a detrimental impact on ovarian physiology. Indeed, sonographic and histologic data tend to support the idea that ovarian follicles of endometriosis patients are decreased in number and more atretic. Moreover, the local intrafollicular environment of patients affected is characterized by alterations of the granulosa cell compartment including reduced P450 aromatase expression and increased intracellular reactive oxygen species generation. However, no comprehensive evaluation of the literature addressing the effect of endometriosis on oocyte quality from both a clinical and a biological perspective has so far been conducted. Based on this systematic review of the literature, oocytes retrieved from women affected by endometriosis are more likely to fail in vitro maturation and to show altered morphology and lower cytoplasmic mitochondrial content compared to women with other causes of infertility. Results from meta-analyses addressing IVF outcomes in women affected would indicate that a reduction in the number of mature oocytes retrieved is associated with endometriosis while a reduction in fertilization rates is more likely to be associated with minimal/mild rather than with moderate/severe disease. However, evidence in this field is still far to be conclusive, especially with regards to the effects of different stages of the disease and to the impact of patients’ previous medical/surgical treatment(s).

Management of Endometriomas Prior to IVF

Endometriosis causes a decrease in fertility in affected patients. The different forms of the disease, peritoneal, ovarian, deep infiltrating and adenomyosis, are often present in varying degrees in the same patient, either together or individually, and cause infertility through a pathogenesis that is not yet clear. A significant number of women with endometriosis and endometriomas will eventually seek assisted reproductive technology (ART) for conception. The specific impact of endometriomas alone and the impact of surgical intervention for endometriomas on the reproductive outcome of women undergoing in vitro fertilization/intra-cytoplasmic sperm injection (IVF/ICSI) are areas that need further clarification and, for this reason, the management of endometriomas before clinical IVF is a very complex topic.

In order to provide useful information for the clinical management of patients with endometriomas having IVF, in this review we investigated: the impact of the presence of endometriomas, both individually and associated with other types of the disease, on IVF techniques; the possible role of surgery and its possible negative effects; the risks and difficulties related to conservative management during IVF procedures.

Strategies to Preserve and Optimize Fertility for Patients with Endometriosis

Endometriosis is commonly associated with dysmenorrhea, chronic pelvic pain, and infertility. When medical therapy fails, surgery is often recommended; unfortunately, endometriosis surgery can adversely impact fertility and ovarian reserve in women desiring future childbearing. This review will focus on mechanisms of infertility in endometriosis patients as well as strategies for optimizing fertility in endometriosis patients when surgery is indicated. In addition, fertility preserving techniques such as oocyte and ovarian tissue cryopreservation as well as issues relevant to in vitro fertilization for patients with endometriosis are discussed.

The impact of endometriosis on the outcome of Assisted Reproductive Technology

BACKGROUND

Endometriosis has been described to impair fertility through various mechanisms. However, studies evaluating the reproductive outcomes of women undergoing assisted reproductive technologies show controversial results. The aim of this study is to assess whether the reproductive outcome is impaired among women with endometriosis-associated infertility undergoing IVF.

METHODS

A retrospective cohort study was performed, including women undergoing IVF reported by the Red Latinoamericana de Reproduccion Asistida (Redlara) registry, between January 2010 and December 2012. The study group included women with endometriosis-associated infertility, and the control group women with tubal factor, endocrine disorders or unexplained infertility. Women above 40 years, severe male factor and premature ovarian failure were excluded. The reproductive outcomes of between both groups were compared. The primary outcome was live birth. Secondary outcomes included clinical pregnancy, miscarriage, number of oocytes retrieved and number of fertilized oocytes. Outcomes were assessed after the first fresh IVF cycle, and were adjusted for age and number of embryos transferred.

RESULTS

A total of 22.416 women were included (3.583 with endometriosis and 18.833 in the control group). Mean age of patients in the endometriosis group and control group was 34.86 (3.47) and 34.61 (3.91) respectively, p = 0.000. The mean number of oocytes retrieved were 8.89 (6.23) and 9.86 (7.02) respectively, p = 0.000. No significant differences were observed between groups in terms of live birth (odds ratio (OR) 1.032, p = 0.556), clinical pregnancy (OR 1.044, p = 0.428) and miscarriage rates (OR 1.049, p = 0.623). Women with endometriosis had significantly lower number of oocytes retrieved (incidence risk ratio (IRR) 0.917, 95% CI 0.895-0.940), however, the number of fertilized oocytes did not differ among the two groups when adjusting for the number of oocytes retrieved (IRR 1.003, p = 0.794). An age-stratified analysis was performed, and no differences were observed in the reproductive outcomes between groups for women aged under 35 and 35 to 40.

CONCLUSIONS

Reproductive outcomes among women undergoing IVF and diagnosed with endometriosis-associated infertility do not differ significantly from women without the disease. Although women with endometriosis generate fewer oocytes, fertilization rate is not impaired and the likelihood of achieving a live birth is also not affected.

The sensitivity of the DNA damage checkpoint prevents oocyte maturation in endometriosis

Mouse oocytes respond to DNA damage by arresting in meiosis I through activity of the Spindle Assembly Checkpoint (SAC) and DNA Damage Response (DDR) pathways. It is currently not known if DNA damage is the primary trigger for arrest, or if the pathway is sensitive to levels of DNA damage experienced physiologically. Here, using follicular fluid from patients with the disease endometriosis, which affects 10% of women and is associated with reduced fertility, we find raised levels of Reactive Oxygen Species (ROS), which generate DNA damage and turn on the DDR-SAC pathway. Only follicular fluid from patients with endometriosis, and not controls, produced ROS and damaged DNA in the oocyte. This activated ATM kinase, leading to SAC mediated metaphase I arrest. Completion of meiosis I could be restored by ROS scavengers, showing this is the primary trigger for arrest and offering a novel clinical therapeutic treatment. This study establishes a clinical relevance to the DDR induced SAC in oocytes. It helps explain how oocytes respond to a highly prevalent human disease and the reduced fertility associated with endometriosis.

Fertile ground: human endometrial programming and lessons in health and disease

The human endometrium is a highly dynamic tissue that is cyclically shed, repaired, regenerated and remodelled, primarily under the orchestration of oestrogen and progesterone, in preparation for embryo implantation. Humans are among the very few species that menstruate and that, consequently, are equipped with unique cellular and molecular mechanisms controlling these cyclic processes. Many reproductive pathologies are specific to menstruating species, and studies in animal models rarely translate to humans. Abnormal remodelling and regeneration of the human endometrium leads to a range of reproductive complications. Furthermore, the processes regulating endometrial remodelling and implantation, including those controlling hormonal impact, breakdown and repair, stem/progenitor cell activation, inflammation and cell invasion have broad applications to other fields. This Review presents current knowledge regarding the normal and abnormal function of the human endometrium. The development of biomarkers for prediction of uterine diseases and pregnancy disorders and future avenues of investigation to improve fertility and enhance endometrial function are also discussed.

Oocyte competence in in vitro fertilization and intracytoplasmic sperm injection patients suffering from endometriosis and its possible association with subsequent treatment outcome: a matched case-control study

INTRODUCTION

Endometriosis affects up to 15% of women of reproductive age. There is an obvious lack of studies dealing with morphological parameters of oocyte morphology in endometriosis patients in assisted reproduction. One aim of the study is to describe oocyte morphology in patients undergoing intracytoplasmic sperm injection suffering from endometriosis. In addition, the impact of endometriosis on in vitro fertilization results is analyzed. Both in vitro fertilization and intracytoplasmic sperm injection patients are then matched with an endometriosis-free control group for highlighting the possible association of endometriosis with pregnancy outcome.

MATERIAL AND METHODS

Oocyte morphology of endometriosis patients was assessed in two groups. Both study group and control group consisted of 129 in vitro fertilization/intracytoplasmic sperm injection cycles each. Patients were matched according to anti-Müllerian hormone, female age, previous treatment cycles, and method of fertilization. Endometriosis was graded according to the revised American Society for Reproductive Medicine guidelines of 1997.

RESULTS

Patients with endometriosis had a significantly lower rate of mature oocytes (p < 0.03) and morphologically normal oocytes (p < 0.001). In particular, brownish oocytes (p < 0.009; stage I-IV) and the presence of refractile bodies (p < 0.001; stage IV) were found to be increased. Endometriosis stage IV was associated with significantly worse-quality oocytes than stages I-III (p < 0.01). Fertilization was significantly reduced in conventional in vitro fertilization but not in intracytoplasmic sperm injection (p < 0.03). This was due to lower fertilization rates in stage III-IV endometriosis compared with stage I-II (p < 0.04). No difference was observed with respect to rates of implantation, clinical pregnancy, miscarriage, live birth, and malformation.

CONCLUSIONS

Endometriosis patients, in particular those with severe endometriosis, present lower-quality oocytes. Once fertilized, no impairment of further preimplantation embryo development and pregnancy outcome right up to healthy live birth rate has to be expected.

Impact of endometriosis on in vitro fertilization outcomes: an evaluation of the Society for Assisted Reproductive Technologies Database

OBJECTIVE

To assess the impact of endometriosis, alone or in combination with other infertility diagnoses, on IVF outcomes.

DESIGN

Population-based retrospective cohort study of cycles from the Society for Assisted Reproductive Technology Clinic Outcome Reporting System database.

SETTING

Not applicable.

PATIENT(S)

A total of 347,185 autologous fresh and frozen assisted reproductive technology cycles from the period 2008-2010.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Oocyte yield, implantation rate, live birth rate.

RESULT(S)

Although cycles of patients with endometriosis constituted 11% of the study sample, the majority (64%) reported a concomitant diagnosis, with male factor (42%), tubal factor (29%), and diminished ovarian reserve (22%) being the most common. Endometriosis, when isolated or with concomitant diagnoses, was associated with lower oocyte yield compared with those with unexplained infertility, tubal factor, and all other infertility diagnoses combined. Women with isolated endometriosis had similar or higher live birth rates compared with those in other diagnostic groups. However, women with endometriosis with concomitant diagnoses had lower implantation rates and live birth rates compared with unexplained infertility, tubal factor, and all other diagnostic groups.

CONCLUSION(S)

Endometriosis is associated with lower oocyte yield, lower implantation rates, and lower pregnancy rates after IVF. However, the association of endometriosis and IVF outcomes is confounded by other infertility diagnoses. Endometriosis, when associated with other alterations in the reproductive tract, has the lowest chance of live birth. In contrast, for the minority of women who have endometriosis in isolation, the live birth rate is similar or slightly higher compared with other infertility diagnoses.

Modern Management of Endometrioma-Associated Infertility: in Favor of ART

Introduction

Endometrioma is present in 17% to 40% of women with endometriosis. Since it has been traditionally believed that the presence of an endometrioma adversely affects the outcome of assisted reproductive technology (ART), surgery has been suggested by many practitioners before advancing to ART, in the hope of improving results.

Scientific Evidence

In the present article, we outline the impact of an endometrioma on the ovarian reserve and describe how surgical resection of an endometriotic cyst affects ovarian reserve, ovarian response after stimulation and ART outcome. Several studies suggest that the sole presence of an endometrioma may have a negative impact on ovarian reserve of the affected ovary, and surgery (particularly cystectomy) has been the choice of treatment in ovarian endometriosis for many years. However, detrimental effects of laparoscopic surgical removal on ovarian reserve and responsiveness to hyperstimulation has made that ART practices are shifting towards a more conservative approach: experimental and clinical data supporting this shift are thoroughly reviewed here.

Clinical Implications

Opposed to the conventional criteria of performing cystectomy when ovarian endometrioma is observed, careful consideration of patient symptoms as well as her age and ovarian reserve will help to select the patients that require surgery prior to ART, whereas the majority will not need surgery prior to ART; even more, surgery may compromise ovarian reserve in most cases even if performed by careful surgeons.

Conclusions

Individualization of the treatment is imperative. Each case should be thoroughly assessed, looking at both the advantages and complications of cyst removal prior to ART. Surgery should be approached with caution in women with endometriomas, especially if the woman has had previous ovarian surgery. In the presence of infertility, we recommend generally sparing surgical treatment and proceeding directly to ART. This reduces the time to achieve a pregnancy, avoids potential surgical risks and limits patient costs.

Effect of Endometriosis on IVF Outcomes in Cases of Single Embryo Transfer for first IVF Attempt in Patients under 35

Background

Implantation disorders are regarded differently in different groups undergoing in vitro fertilization (IVF) because of heterogeneous patient populations. To avoid this problem, this study was based solely on the first attempts of a single embryo transfer in patients under the age of 35.

Methods

This was a retrospective comparative study with 2 groups of patients: a group with endometriosis (n = 288) and a group without endometriosis (n = 1,368), registered from January 2010 to December 2013 in the IVF center of the University Hospital of Clermont-Ferrand. This study compared the 2 groups and subgroups according to ovarian response and embryo quality, and analyzed oocyte number, embryo number, transfer rate, implantation rate and delivery rate per ovum pick-up and per transfer.

Results

In the cases of endometriosis, the number of collected oocytes (8.37 ± 7.01 vs. 10.13 ± 6.53 p<0.001), the transfer rate (81.4% vs. 86.1%, p = 0. 045) and the rate of cycles with a frozen embryo (48.9% vs. 57.3%, p<0.01) were lower. The probability of a satisfactory response to stimulation (70.7% vs. 81.0%, p<0.001) and of a good quality embryo cohort (45% vs. 52%, p = 0.003) was lower. However, the implantation and delivery rates per transfer were not distorted in the cases of endometriosis, either in the total group or in any subgroup. The cumulative live birth rate per attempt was similar (29.2% vs. 29.5%).

Conclusions

Endometriosis has no impact on the embryo transfer in IVF, particularly when the embryo quality is satisfactory.