Endometrial Receptivity Array Research Articles

A Comprehensive Review of the Endometrial Receptivity Array in Euploid Embryo Transfer Cycles

A Comprehensive Review of the Endometrial Receptivity Array in Euploid Embryo Transfer Cycles

Endometrial Receptivity Array—A Promising Remedy for Women Afflicted with Recurrent Implantation Failure: A Case Report

Endometrial Receptivity Array—A Promising Remedy for Women Afflicted with Recurrent Implantation Failure: A Case Report

Case Report: The combined effect of endometrial receptivity array and laser assisted hatching on embryo implantation in repeated implantation failure case

This case report describes a couple with nine years of primary infertility and three failed in vitro fertilization (IVF) attempts that showed no reproductive abnormality. Negative results were observed following the conventional IVF protocol. The couple then insisted on laser-assisted hatching (LAH) and endometrial receptivity analysis (ERA). The ERA results showed a specific window for embryo implantation, and accordingly, the treatment was carried out, which resulted in seven good-quality oocytes, leading to the formation of four blastocyst-stage embryos. These embryos were then frozen, single embryo transfer (ET) was performed following the ERA results, and the embryos were successfully implanted. The βhCG level was 245 mIU/mL, indicating that the female had successfully conceived. This case highlights the challenges of a thick zona pellucida and recurrent implantation failure (RIF), defining how a personalized method combining both LAH and ERA could lead to successful implantation.

Exploring the effectiveness of endometrial receptivity array and immune profiling in patients with multiple implantation failure：A retrospective cohort study based on propensity score matching

This study aimed to evaluate the effectiveness of the endometrial receptivity array (ERA), endometrial immune profiling, and a combination of both in improving the pregnancy outcomes for multiple implantation failure patients. According to patients’ willingness, 1429 women who incurred at least two or more consecutive implantation failures in IVF/ICSI treatment opted for frozen embryo transfer and were divided into four groups: ‘No test’, ‘Immune Profiling’, ‘ERA’ and ‘ERA+ Immune Profiling’. Women in three test groups underwent timed endometrial biopsy for ERA, immune profiling, a combination of both. We observed the overall incidence rates of the displaced window of implantation (WOI) and endometrial immune dysregulation were 75.14% and 79.29%, respectively. After 1:1 propensity score matching (PSM), our data revealed that the ‘ERA’ and ‘ERA + Immune Profiling’ groups demonstrated significantly higher rates of biochemical, clinical, ongoing pregnancy, and implantation compared to the ‘No test’ group (p < 0.01). The ‘Immune Profiling’ group showed a higher implantation rate compared to ‘No test’ group (p < 0.05). Furthermore, when comparing three test groups, the ‘ERA + Immune Profiling’ group exhibited notably higher rates of clinical and ongoing pregnancy compared to the ‘Immune Profiling’ group (p < 0.017). However, there was no association between endometrial immune profiling and ERA phases, and their results did not differ between embryo implantation and non-implantation in these patients. Our findings underline the increased implantation rates by use of ERA and endometrial immune profiling in patients with multiple implantation failure, either individually or corporately. Moreover, a combination of both could improve their pregnancy outcomes significantly.

What is the Optimum Endometrium Needed for Implantation?

Implantation most critical step in reproduction. A complex process where blastocyst becomes intimately connected with maternal endometrium/decidua and requires; Competent embryo at blastocyst stage Receptive endometrium Synchronized dialogue between maternal and embryonic tissues Endometrial Changes for Implantation include architectural, morphological, cytochemical, molecular and genetic. These Changes Induce Endometrial receptivity, which is endometrial lining in a state of readiness for blastocyst implantation. It involves acquisition of adhesion ligands and loss of inhibitory components that may act as a barrier to an attaching embryo. Receptive endometrium is capable of selecting good quality embryos and reject the incompetent embryos. Endometrial Evaluation includes 1. Non-Invasive Assessment of Endometrial Receptivity by USG 2. Detection of abnormal Uterine cavity by 3D USG/SIS, HSG and Hysteroscopy 3. Diagnose Chronic Endometritis by hysteroscopy and Molecular tests? 4. Endometrial Microbiome by molecular tests 5. Endometrial asynchrony - Proteomics and transcriptomics 2D and 3D Ultrasound can Identify patients with poor implantation prognosis but has low predictive value in determining endometrial receptivity and IVF outcome. Ideal endometrial thickness for optimal outcome is between 7-14 mm. No Association was seen between clinical pregnancy rates (CPR) and endometrial pattern for women undergoing in IVF with fresh ET and FET. Minimum Endometrial Volume associated with pregnancy is 1.59 mL – 3D. But most pregnancies occur in volumes of 2-13 mL. Evaluation of endometrial volume is particularly useful in synechiae, adenomyosis and uterine anomalies. Vascularity demonstrated within Zone 3 or within Zones 3 and 4 prior to transfer is associated with good implantation rate. Presence of &gt;3 peristaltic contractions of the sub endometrial myometrium/2 minutes interval on Day of hCG administration associated with poor implantation. Diagnosis of chronic endometritis is based on hysteroscopy, endometrial biopsy with plasma cells being identified histologically and specific treatment is determined based on microbial culture. Existence of non-Lactobacillus bacteria in the endometrium is correlated with negative impacts on reproductive function and should be considered as an emerging cause of implantation failure and pregnancy loss. Endometrial Receptivity Array (ERA) is validated for analysing the expression of 238 genes that are intimately related to endometrial receptivity. Abnormality in endometrial receptivity is displayed a specific gene expression profile. Intrauterine secretory profile directly linked to successful implantation and evaluation of endometrial fluid for cytokine, interleukin and growth factor secretions can be used to assess the endometrium. Conclusion: Identification of one or more of endometrial parameters that definitely indicate receptivity for implantation remains an elusive goal. None of the endometrial receptivity markers have sufficient discriminatory value to act as a diagnostic test for endometrial receptivity based on their ability to predict clinical pregnancy. Due to the dynamic, cyclic nature of the endometrium it may be difficult, to reliably assess endometrial function on the basis of a single test.

Factors affecting the ongoing pregnancy rate in women with repeated implantation failure undergoing an endometrial receptivity array.

In this retrospective study, we analyzed factors influencing the ongoing pregnancy rate (PR) in women with repeated implantation failure (RIF) undergoing embryo transfer with endometrial receptivity array (ERA). Eighty-three consecutive personalized embryo transfers (pETs) with ERA, from 54 women with RIF, were selected from June 2020 to April 2022. Vitrified blastocyst transfer was timed based on ERA results. The ongoing PR per pET was 33.7%. Using ERA, the endometrium was identified as pre-receptive in 26 cycles, early receptive in 25 cycles, receptive in 31 cycles, and late receptive in one cycle. With cycles categorized into three receptivity phases (pre-receptive, early receptive, or receptive), no significant differences were found in the clinical PR (27.3%, 55.6%, and 40%, respectively) or ongoing PR (9.1%, 55.6%, and 40%, respectively) after a single blastocyst transfer. Similarly, no significant differences were observed in the clinical PR or ongoing PR after the transfer of two or more blastocysts. Among women with ongoing pregnancy relative to those without, age at first pET was significantly lower (35 years vs. 39 years, p=0.001), while blastocyst score (23 vs. 18, p=0.012) and the proportion of blastocyst scores >18 (71.4% vs. 38.9%, p=0.005) were significantly higher. In multiple logistic regression analysis, the woman's age (odds ratio [OR], 0.814; 95% confidence interval [CI], 0.706 to 0.940; p=0.005) and blastocyst score >18 (OR, 3.052; 95% CI, 1.075 to 8.665; p=0.036) were identified as significant factors influencing ongoing pregnancy. In pET with ERA, ongoing pregnancy was closely associated with woman's age and blastocyst quality.

Consistency of endometrial receptivity array and histologic dating of spatially distinct endometrial samplings: a prospective, blinded study

To compare the consistency of endometrial receptivity array (ERA) and histologic dating among 3 spatially distinct endometrial samples obtained during a cycle of exogenous estrogen and progesterone. Prospective blinded study. University practice. Twelve patients undergoing a mock frozen embryo transfer cycle. Endometrial biopsy was performed in a manner that provided a spatially organized endometrial specimen, corresponding to the fundus, middle, and lower segment. Each of these 3 sections was further divided into immediately adjacent specimens for ERA and histology. Consistency of the ERA and histology results among fundal, mid, and lower endometrial biopsy specimens. The ERA showed variability in outcome among different patients but dated all specimens originating from the same patient identically. Histologic dating showed variability between patients as well as between different locations within the uterus. When comparing average dating results for each patient, we saw a positive correlation between histologic and ERA dating (Spearman Rho= 0.45); however, this did not reach statistical significance. The ERA results from upper, mid, and lower uterine biopsy specimens were identical for each autologous biopsy, whereas histologic dating showed variability with an average standard deviation of 0.71days. The increased heterogeneity of histologic dating is likely to be attributed to the subjectivity of the test. Furthermore, we did not observe a consistent lag or advancement in histologic or ERA dating between the fundal or lower uterine biopsies. Overall, cliniciansshould be reassured that endometrial tissue will return consistent ERA results independent of the location within the uterus in which it was obtained.

P-533 Comparison of Endometrial Receptivity Array (ERA) with Preimplantation genetic testing (PGT) versus ERA alone in improving outcomes in Recurrent implantation failure.

Abstract Study question Whether addition of Preimplantation Genetic Testing for aneuploidy (PGT-A) to Endometrial Receptivity Array (ERA) helps in improving success rates in Recurrent Implantation Failure (RIF) patients. Summary answer Addition of PGT-A intervention to ERA in RIF patients did not improve outcomes. What is known already RIF causes great emotional stress and financial burden for the infertile couple. Successful implantation requires a synchronous interaction between a competent blastocyst and a receptive endometrium. Though ERA, as a measure to assess window of implantation (WOI), is around a decade old, its role in improving success rates in patients with RIF is still controversial. PGT-A, as a tool for selecting euploid embryos, though has shown to be beneficial in women with advanced maternal age, its role in improving success rates in RIF needs further evaluation. Study design, size, duration This is a multicenter retrospective cohort study carried out from September 2015 till September 2022. 285 patients with RIF with previous failed transfers with ≥ 3 good quality embryos were included. Participants/materials, setting, methods 285 patients with RIF were divided into 2 groups. Group 1 underwent PGT-A and Personalised Embryo Transfer (pET) guided by ERA and Group 2 underwent only ERA followed by pET. In Group 1 patients, embryo biopsy was done on day 5 and day 6 blastocyst before cryopreservation and NGS platform was used to detect euploid embryos. Both groups then underwent ERA followed by pET in the next cycle. Main results and the role of chance In total of 285 RIF patients studied, 59.2% patients showed displaced WOI. 91.7% ERA reports were pre-receptive. Group 1 included 137 patients and Group 2 had 148 patients &amp; baseline characteristics were similar in both the groups. Group 1 had more self transfer cycles, i.e. 76.7% self and 17.2% donor oocytes, as compared to Group 2 with 40.2% self and 30.7% donor oocyte cycles. The implantation rate (IR), live birth rate (LBR), miscarriage rate and cumulative LBR were similar in both the groups. Higher Pregnancy rate (PR) in Group 2 (70.9% vs 57.83%) could be attributed to higher donor cycles in this group. Multiple gestation rate was also higher in Group 2 (31.49% vs 11.21%) as 2 blastocysts were transferred in most cycles in group 2 compared to Single embryo transfer(SET) in most cycles in Group 1. As PR was higher in ERA group, subgroup analysis of self gamete transfers and donor oocyte transfers was also done, which showed similar PR, IR and LBR in both the groups. Hence, PGT failed to show any value in improving pregnancy outcomes in RIF. Limitations, reasons for caution Retrospective study design. Wider implications of the findings The role of PGT in improving clinical outcomes in RIF patients needs to be studied in larger prospective studies. In our study, ERA as an intervention improved outcomes in RIF. Trial registration number not applicable

P-485 Performance of ERA test after PGT-A in RIF patients defined according to ESHRE 2023 good practice recommendations: a retrospective case-control study

Abstract Study question Is Endometrial-Receptivity-Array (ERA) test clinically-useful among Repeated-Implantation-Failure (RIF) women defined according to ESHRE 2023 good-practice-recommendations (GPR) and undergoing single euploid blastocyst transfer? Summary answer ERA-test showed a higher “non-receptive endometrium” rate among RIF. Nevertheless, the live-birth-rate (LBR) per first euploid transfer was independent from progesterone timing according to ERA-test. What is known already ERA-test evaluates the expression of 238 genes from an endometrial biopsy. It aims at predicting the window of implantation and adjust progesterone timing accordingly. The data are controversial due to poor study design and/or limited sample size. Few studies investigated ERA-test in a setting with euploid transfers and/or among RIF patients. Moreover, RIF definition is largely inconsistent leading to a significant bias in the interpretation of the existing literature and treatment. ESHRE 2023 GPR revised RIF definition. Here, we leveraged this updated definition and PGT-A to assess ERA-test diagnostic/therapeutic performance in these women. Study design, size, duration Retrospective case-control study during 2013-2021 including 2211 patients with at least one euploid blastocyst after PGT-A. Hysteroscopy was conducted in case of suspect uterine pathologies, biopsy in case of suspect inflammation, and therapy in case of endometritis. 265 patients (12%) were classified RIF according to the ESHRE GPR (= no successful implantation despite an estimated cumulative chance ≥60%). 48 RIF patients requested ERA-test before undergoing vitrified-warmed euploid single blastocyst transfer, while 217 did not. Participants/materials, setting, methods qPCR/NGS-based PGT-A was conducted to assess non-mosaic aneuploidies. Normal thyroid function, vitamin-D levels, uterine cavity, and absence of sactosalpynx were confirmed. Whenever the ERA test suggested altered receptivity, progesterone timing was modified accordingly. The primary outcome was LBR per first euploid transfer in the non-ERA versus ERA groups, with a sub-analysis in ERA receptive versus non-receptive. Outcomes were adjusted for confounders assessed via logistic regressions. Main results and the role of chance RIF patients requesting ERA-test were older (39.1±4.5 versus 36.7±3.5 years, p &amp;lt; 0.01), and had already undergone 3.7±2.0 transfers resulted in implantation failures (1.5±1.3 of euploid blastocysts) versus 2.6±1.7 transfers (1.0±0.8 of which of euploid blastocysts) in the control (p &amp;lt; 0.01). Nevertheless, all these variables were not associated with the primary outcome under investigation. 44 non-RIF patients requested ERA-test in the same study period. Notably, the rate of pre-/post-receptive endometria was 39.6% (N = 19/48) among RIF and 13.6% (N = 6/44) among non-RIF women (p &amp;lt; 0.01). In fact, maternal age was not associated with “non-receptive” responses after ERA-test, the number of previous implantation failures showed an Odds-Ratio 1.29, 95%CI 1.03-1.62, p = 0.03. Blastocyst quality and day of full-blastulation were similar in ERA and non-ERA patients, as well as in ERA receptive and non-receptive patients. Positive pregnancy test, biochemical-pregnancy-loss, and miscarriage rates were all similar among non-ERA and ERA, and among ERA receptive and non-receptive patients. Indeed, also the LBR was similar among non-ERA and ERA (N = 98/220, 44.5% versus N = 17/48, 35.4%, p = 0.26; Odds-Ratio adjusted for blastocyst quality and day of full-blastulation: 0.76, 95%CI:0.39.1.48, p = 0.42) and among ERA receptive and non-receptive patients (N = 10/29, 34.5% versus N = 7/19, 36.8%, p = 0.99; Odds-Ratio adjusted for blastocyst quality and day of full-blastulation: 0.99, 95%CI:0.3-3.4, p = 0.99). Limitations, reasons for caution Our standard clinical workflow does not entail ERA-test, but the couple may request it. The study is retrospective with limited sample size. Patients requesting ERA-test were older with more previous failures. Non-ERA and ERA receptive patients underwent either Hormone-Replacement-Therapy or Modified-Natural-Cycle. Cost-effectiveness analyses are missing. Wider implications of the findings A promising association was reported between the novel definition of RIF and “non-receptive” responses, suggesting that ERA-test might unveil endometrial receptivity issues. Nevertheless, positive, and negative predictive values upon implantation are largely missing and its clinical utility as a therapeutic tool in RIF women remains questionable. Trial registration number none

P-526 Modified Applebaum uterine scoring system to predict uterine receptivity in frozen embryo transfer(FET) cycles

Abstract Study question To evaluate modified Applebaum uterine scoring system in predicting the uterine receptivity and clinical pregnancy rate? Summary answer The modified version of Applebaum uterine scoring system has sensitivity of 0.9411 and specificity of 0.5869 in predicting the uterine receptivity in embryo transfer cycle. What is known already The endometrial receptivity have been accepted to be major limiting factors in the establishment of pregnancy. Different techniques have been developed to evaluate endometrial receptivity, such as endometrial receptivity array or histological dating. The advantage of Ultrasound is it’s non-invasiveness, repeatability, real time monitoring and predictability. Study design, size, duration It is a prospective observational study. Study group comprises of 200 female with primary infertility over a period of 6 month. Participants/materials, setting, methods Exclusion criteria was patients associated with male sub-fertility or having uterine anomalies. The study was conducted at D.Y.Patil fertility centre, unit of Bloom IVF. All the patients were given uterine scoring before FET based on Endometrial thickness, morphology, vascularisation, myometrial echogenicity, uterine artery PI and EDF, myometrial blood flow. Main results and the role of chance The overall pregnancy rate was 54%. A perfect score of 20 was associated with 97.4% pregnancy rate. Scores of 17 to 19 was associated with the pregnancy rate of 85.4% and scores of 14 to 16 was associated with the pregnancy rate of 28.6%. Score less than 13 is not associated with any pregnancy. The Modified Applebaum scoring system showed the sensitivity of 0.9411 and specificity of 0.5869 in predicting the outcome of the cycle. On an individual basis, endometrial morphology, end diastolic blood flow(EDF) and Pulsatility index(PI) of uterine artery and myometrial blood flow were found to be significant for a pregnancy on the basis of Z score and p value of &amp;lt; 0.01 Limitations, reasons for caution As there were no case of secondary infertility, Grade III/IV endometriosis, endocrine disorder and uterine anomalies. The scoring system might not replicate the same results. Wider implications of the findings As the sensitivity and specificity of this uterine scoring system is quite good. It could be a good tool in assessing endometrium before embryo transfer. Trial registration number Not applicable

Review of Endometrial Receptivity Array: A Personalized Approach to Embryo Transfer and Its Clinical Applications.

Successful outcomes of in vitro fertilization (IVF) rely on both the formation of a chromosomally normal embryo and its implantation in a receptive endometrium. Pre-implantation genetic testing for aneuploidy (PGT-A) has been widely accepted as a tool to assess the viability of an embryo. In 2011, the endometrial receptivity array (ERA) was first published as a tool to determine when the endometrium is most receptive to an embryo, commonly referred to as the "window of implantation" (WOI). The ERA uses molecular arrays to assess proliferation and differentiation in the endometrium and screens for inflammatory markers. Unlike PGT-A, there has been dissent within the field concerning the efficacy of the ERA. Many studies that contest the success of the ERA found that it did not improve pregnancy outcomes in patients with an already-good prognosis. Alternatively, studies that utilized the ERA in patients with repeated implantation failure (RIF) and transfer of known euploid embryos demonstrated improved outcomes. This review aims to describe the ERA as a novel technique, review the various settings that the ERA may be used in, such as natural frozen embryo transfer (nFET) and hormone replacement therapy frozen embryo transfer (HRT-FET), and provide a summary of the recent clinical data for embryo transfers in patients with RIF utilizing the ERA.

Potential Biomarkers and Endometrial Immune Microenvironment in Recurrent Implantation Failure

The molecular mechanisms underlying unexplained recurrent implantation failure (RIF) remain unclear. This study aimed at identifying potential biomarkers, exploring relevant signaling pathways, and analyzing the contribution of immune cell infiltration in RIF. Microarray expression datasets were extracted from the Gene Expression Omnibus database to perform bioinformatic analyses. The results showed that ten hub genes may predict RIF with high specificity and sensitivity (area under the curve = 1.000). Protein-protein interaction analysis revealed close interactions between the hub genes and the endometrial receptivity array. The real-time quantitative polymerase chain reaction further validated three potential biomarkers (RAB32, TRIB2, and FAM155B). Functional enrichment analyses indicated that immune pathways were significantly downregulated and lipid metabolism pathways were significantly upregulated in RIF compared with the controls. Significant negative correlations were observed between fatty acid biosynthesis and the immune pathways. Immune cell infiltration, including those in CD56dim natural killer, dendritic, Th1, Th2, and regulatory T cells, as well as macrophages, was significantly reduced in RIF compared with the controls used herein. This study may provide a novel perspective on the diagnosis and treatment of RIF.

Personalized versus standard frozen-thawed embryo transfer in IVF/ICSI cycles: a systematic review and meta-analysis.

To investigate whether personalized embryo transfer (pET) protocol guided by an endometrial receptivity array (ERA) can improve clinical outcomes of assisted reproduction. We searched PubMed, Embase, Web of Science, and the Cochrane library for studies in which analytical comparisons of outcomes of pET and standard embryo transfer (sET) groups were undertaken. The references to the included studies were also manually searched. The primary outcome was clinical pregnancy rate (CPR), and the secondary outcomes were live birth rate (LBR), human chorionic gonadotropin (HCG) positivity, biochemical pregnancy rate (BPR), miscarriage rate (MR), implantation rate (IR), and ongoing pregnancy rate (OPR). Ten studies were included in the meta-analysis, including one randomized controlled trial (RCT) and nine cohort studies. We observed no significant difference in the primary outcome of CPR between the pET and sET groups in unselected patients (RR = 1.07; 95% confidence interval [CI], 0.87-1.30; P = 0.53; I2 = 89%). In terms of secondary outcomes, we likewise noted no significant differences between the groups. Further subgroup analyses indicated that the pET protocol not only significantly reduced the MR for poor-prognosis patients, but it also reduced the CPR in donor cycles, elevated the BPR for good-prognosis patients, non-preimplantation genetic testing (PGT), and programmed cycles, and decreased the proportion of women showing HCG positivity in non-PGT cycles. This meta-analysis revealed that ERA appears to possess limited guidance in embryo transfer. More high-quality RCTs are therefore needed to investigate the clinical validity and feasibility of ERA in the future.

Use of the Endometrial Receptivity Array to Guide Personalized Embryo Transfer After a Failed Transfer Attempt Was Associated With a Lower Cumulative and Per Transfer Live Birth Rate During Donor and Autologous Cycles

(Abstracted from Fertil Steril 2022;118(4):724–736) Although preimplantation genetic testing for aneuploidy increases the likelihood of live birth per embryo transfer in in vitro fertilization, a euploid embryo does not guarantee success. Endometrial factors including timing transfer during the “implantation window” contribute to the likelihood of achieving pregnancy.

Effects of Hydrosalpinx on Endometrial Receptivity and Uterine Microbiome: An Interesting Case of Double Uterus with Unilateral Hydrosalpinx

Endometrial receptivity array (ERA)—an objective tool used in assisted reproductive technology—is used for personalized embryo transfer in in vitro fertilization. Hydrosalpinx affects implantation through various mechanisms. However, its effects on ERA are not well established. In this case report, we present the diagnosis and treatment of a 34-year-old nulligravida woman with infertility for two years, obesity, double uterus with unilateral hydrosalpinx and right kidney deficiency. Based on ERA results, endometrial microbiome metagenomic analysis (EMMA), analysis of infectious chronic endometritis (ALICE), and CD138 immunostaining, the patient was treated with hormonal replacement cycle and amoxicillin/clavulanic acid. After one week of amoxicillin/clavulanic acid administration, the vitirified-warmed 4AA blastocyst was transferred to the left uterus—which was absent of hydrosalpinx and easily accessible to transfer and pregnancy was achieved. To the best of our knowledge, this case study is the first one in which we found that there were no differences between the left and right uterus in ERA, EMMA, ALICE, and CD138 immunostainings. Hence, we suggest that hydrosalpinx does not necessarily cause endometrial changes in all cases. Further research to evaluate the effects of hydrosalpinx on implantation with ERA and EMMA/ALICE is warranted.

Executive Editor-in-Chief’s introduction for This Special Issue

Executive Editor-in-Chief’s introduction for This Special Issue

Use of the endometrial receptivity array to guide personalized embryo transfer after a failed transfer attempt was associated with a lower cumulative and per transfer live birth rate during donor and autologous cycles

To determine whether personalized embryo transfer (pET) guided by endometrial receptivity array (ERA) test improves reproductive outcomes for fresh embryo transfers (fsETs) or frozen embryo transfers (FETs) during autologous and donor cycles. A retrospective, observational, multicenter cohort study. University-affiliated invitro fertilization center. The study included patients with a single previous failed transfer and yielded 3,239 autologous transfers and 2,133 donor transfers. Among autologous transfers, 255 were pET guided by ERA; among unguided autologous transfers, 1,122 and 1,862 transfers involved fresh or previously frozen embryos, respectively. Among donor transfers, 319 were ERA-guided; among unguided donor transfers, 1,175 and 639 involved fsETs or FETs, respectively. None. Primary outcomes were live birth rate per embryo transfer and cumulative live birth rate on consecutive transfers until live birth or cessation of pregnancy. Secondary outcomes were implantation, pregnancy rate, clinical pregnancy rates per embryo transfer, and miscarriage rate per pregnancy. During both autologous or donor transfers, live birth rate and cumulative live birth rate were higher in FET and fsET than in pET groups, even with euploid transfers. Logistic regression analysis, considering possible confounders, indicated patients receiving pET had poorer outcomes than those undergoing FET and fsET in autologous and donor cycles. Implantation, pregnancy, and clinical pregnancy rates were lower in patients undergoing pET. Using ERA to guide pET during either autologous or donor cycles after a failed transfer attempt did not improve reproductive outcomes. Conversely, worse outcomes were detected when ERA was used.

Lipid metabolism-related genes as biomarkers and therapeutic targets reveal endometrial receptivity and immune microenvironment in women with reproductive dysfunction.

In recent years, alterations in lipid metabolism are currently considered a hallmark feature of many diseases. However, the role in women with reproductive dysfunction (WRD) remains to be fully elucidated. Here, this study aimed to explore the effect of lipid metabolism-related genes (LMRGs) on endometrial receptivity of WRD. This study retrospectively analyzed endometrial receptivity array (ERA) in GEO database. The differential expression genes (DEGs) were obtained by limma differential analysis, and the core genes and corresponding predicted microRNA were obtained through protein-protein interaction (PPI) analysis and TargetScan database, so as to predict the chemical targets of drug therapy. Through the intersection of DEGs and LMRGs, the target gene expression profile was obtained for subsequent consensus clustering analysis and immune analysis. In addition, the immune cell infiltration was assessed by applying the ESTIMATE and MCPcounter algorithm and potential drug targets were obtained from the HERB website. 1473 genes showed differential expression between the groups of WRD and fertile women, and then a large number of lipid metabolism-related pathways and immune-related pathways were enriched. Twelve core genes and corresponding predicted miR-134-3p were obtained; most importantly, we found that these 12 genes were all LMRGs. Through drug target prediction, we obtained three drugs that regulate lipid metabolism and improve blood circulation, namely lovastatin, estrogen, and quercetin. EHHADH (AUC = 0.85) and PTEN (AUC = 0.82) have the best diagnostic performance. UMAP and heatmap revealed large differences between three clusters. LMRGs revealed specific manifestations of WRD in endometrial receptivity and immune microenvironment. Our study explored the expression pattern of LMRGs in endometrium of WRD, screened the corresponding biomarkers, and proposed the combination of traditional Chinese and Western medicine to improve the endometrial receptivity.

Personalized Embryo Transfer Outcomes in Recurrent Implantation Failure Patients Following Endometrial Receptivity Array With Pre-Implantation Genetic Testing.

IntroductionImplantation failure is a trending problem for pregnancy outcomes. Women's reproduction rates can increase by in-vitro fertilization, which comes with frequent implantation failures. These failures can be mitigated by the personalization of embryo transfer depending on the patient's implantation window. The study aimed to assess the importance of using an endometrial receptivity array (ERA) combined with pre-implantation genetic testing in patients with recurrent implantation failure (RIF) and the significant role of personalized embryo transfer (PET) after ERA in patients with a displaced window of implantation. The study also determined the efficacy of this approach in improving clinical outcomes.MethodsWe conducted this observational retrospective study following approval by the Ethics Committee of Wings In-Vitro Fertilization (IVF) Women's Hospital, a unit of Reveba Infertility Clinics Pvt. Ltd., Ahmadabad (Approval No. 2019/002/31B). Two hundred ninety-one RIF patients were recruited and categorized into Group I (patients without ERA group) and Group II (ERA study group). Patients in the ERA study group were screened for ERA and subclassified into receptive and nonreceptive ERA groups. PET was performed for all subjects in the ERA study group according to their receptivity as assessed by ERA. We also screened some of the patients for ploidy (genetic) status of embryos by pre-implantation genetic testing for aneuploidy (PGT-A) before embryo transfer. The study had a power of 95% and an alpha of 0.05; therefore, 80 ± 2 subjects were required to conduct the study. ResultsThe primary outcome was the clinical pregnancy rate followed by the implantation rate. We found an improved clinical pregnancy rate and implantation rate (73.5% and 78.6%) in the nonreceptive endometrial group after adjusting their embryo transfer schedule to their endometrial receptivity. The clinical pregnancy rate (64% and 65%) and implantation rate (65% and 74%) in receptive and nonreceptive ERA (respectively) were high in subjects with donor oocytes for IVF/intracytoplasmic sperm injection. In addition, patients who opted for PGT-A to eliminate the risk of transferring aneuploidy embryos had significantly better implantation (88% and 95% receptive and nonreceptive, respectively) and clinical pregnancy rates (100% in both groups) compared to non-PGT-A screened patients (p<0.05; 34% and 37% clinical pregnancy rate, 96% and 57% implantation rate in receptive and nonreceptive groups, respectively).ConclusionEndometrial receptivity assessment is a highly beneficial method to assess the genetic expression of the endometrium and embryo transfer timing. In our study, in patients with recurrent implantation failure, this technology found receptivity issues and provided a chance to plan embryo transfer according to the window of implantation. The combination of PGT-A with ERA rules out the genetic issues related to embryos. In RIF patients, ERA results-guided PET improved the implantation rate and reproductive outcomes.

Endometrial HLA-F expression is influenced by genotypes and correlates differently with immune cell infiltration in IVF and recurrent implantation failure patients.

Is human leukocyte antigen (HLA)-F protein expressed in mid-secretory endometrium, and are its expression levels influenced by HLA-F gene polymorphisms and correlated with the abundance of uterine natural killer (uNK) cells and anti-inflammatory M2 macrophages? HLA-F protein is expressed in mid-secretory endometrium, and levels are correlated with immune cell infiltration, plasma progesterone concentrations and HLA-F single-nucleotide polymorphisms (SNPs), however, women experiencing recurrent implantation failure (RIF) show differences when compared to women attending their first IVF treatment. The immunomodulatory HLA class Ib molecules HLA-G and HLA-F are expressed on the extravillous trophoblast cells and interact with receptors on maternal immune cells. Little is known regarding HLA-F expression in endometrial stroma and HLA-F function; furthermore, HLA-F and HLA-G SNP genotypes and haplotypes have been correlated with differences in time-to-pregnancy. Primary endometrial stromal cell (ESC) cultures (n = 5) were established from endometrial biopsies from women attending IVF treatment at a fertility clinic. Basic HLA-F and HLA-G protein expression by the ESCs were investigated. A prospective controlled cohort study was performed including 85 women with a history of RIF and 36 control women beginning their first fertility treatment and with no history of RIF. In some analyses, the RIF group was divided into unknown cause, male infertility, female infertility, and both female and male infertility. Endometrial biopsies and blood samples were obtained the day equivalent to embryo transfer in a hormone-substituted cycle. HLA protein expression by ESCs was characterized using flow cytometry and western blot. In the cohort study, the specific immune markers HLA-F and HLA-G, CD56 and CD16 (NK cells), CD163 (M2 macrophages), FOXP3 (regulatory T cells) and CD138 (plasma cells) were analysed by immunohistochemistry and a digital image analysis system in endometrial biopsies. Endometrial receptivity was assessed by an endometrial receptivity array test (the ERA® test). Endometrial biopsies were examined according to modified Noyes' criteria. SNPs at the HLA-F gene and HLA-G haplotypes were determined. HLA-F protein is expressed in the endometrium at the time of implantation. Furthermore, the HLA-F protein levels were different according to the womeńs HLA-F SNP genotypes and diplotypes, which have previously been correlated with differences in time-to-pregnancy. Endometrial HLA-F was positively correlated with anti-inflammatory CD163+ M2 macrophage infiltration and CD56+ uNK cell abundance for the entire cohort. However, this was not the case for CD56+ in the female infertility RIF subgroup. HLA-F levels in the endometrial stroma were negatively correlated with plasma progesterone concentrations in the RIF subgroup with known female infertility. Conversely, HLA-F and progesterone were positively correlated in the RIF subgroup with infertility of the male partner and no infertility diagnosis of the woman indicating interconnections between progesterone, HLA-F and immune cell infiltration. Glandular sHLA-G expression was also positively correlated with uNK cell abundance in the RIF subgroup with no female infertility but negatively correlated in the RIF subgroup with a female infertility diagnosis. Immunohistochemistry analyses of endometrial biopsies and DNA sequencing of HLA genes. Data will be shared upon reasonable request to the corresponding author. The control group of women attending their first IVF treatment had an anticipated good prognosis but was not proven fertile. A significant age difference between the RIF group and the IVF group reflects the longer treatment period for women with a history of RIF. The standardization of hormonal endometrial preparation, which allowed consistent timing of endometrial and blood sampling, might be a strength because a more uniform hormonal background may more clearly show an influence on the immune marker profile and HLA class Ib levels in the endometrium by other factors, for example genetic polymorphisms. However, the immune marker profile might be different during a normal cycle. The findings further highlight the importance of HLA-F and HLA-G at the implantation site and in early pregnancy for pregnancy success. Diagnostic measures and modulation of the complex interactions between HLA class Ib molecules, maternal immune cells and hormonal factors may have potential to improve fertility treatment. This work was supported by the Region Zealand Health Sciences Research Foundation and the Zealand University Hospital through the ReproHealth Research Consortium ZUH. The authors declared there are no conflicts of interest.