Treatment Of Recurrent Implantation Failure Research Articles

Assessment of the implantation window and embryonic factor impact to the treatment of recurrent implantation failure (RIF). A prospective study

The aim: to study of the prognostic value of endometrial receptivity and preimplantation genetic diagnosis of embryos, and their influence on the effectiveness of in vitro fertilization (IVF) programs. We also evaluate the importance of this factor in comparison with other potential causes of infertility. Materials and methods: This prospective cohort study included 123 infertile women who underwent in vitro fertilization (IVF) treatment. 93 patients had repeated unsuccessful implantation attempts and were divided into three groups: group 1 - patients who were treated using genetically untested embryos according to a standard fixed stimulation protocol, group 2 - patients who were treated using euploid embryos after preimplantation genetic screening according to standard fixed protocol; group 3 - patients who underwent treatment using euploid embryos after pre-implantation genetic screening and determination of the implantation window with subsequent modification of the stimulation protocol, according to the endometrial examination result. 30 patients had a first attempt at IVF, which was carried out using genetically untested embryos, according to a standard fixed protocol, and made up the control group (CG). Determination of the window of implantation was carried out by triple aspiration biopsy of the endometrium during the luteal phase of the menstrual cycle since the endometrium is most susceptible to implantation during this period. Samples were analyzed using scanning electron microscopy. Based on the results obtained, the endometrial preparation protocol was individualized for the next attempt. preimplantation genetic testing (PGT) of embryos was carried out by the next generation (NGS) method. Statistical analysis was performed using IBM SPSS V25.0 for Windows software. Results: According to the obtained results, patient characteristics, screening rates, IVF cycle characteristics, and the number, quality, and stage of transferred embryos were compared between groups. The rate of clinical pregnancy was 46.7 % among patients of group 1.70 % among patients of group 2, 82.8 % among patients of group 3 and 50.0 % of the control group and statistically significantly different between groups (χ2=10.955, p= 0.012). The rate of live birth was 43.3 % among patients of group 1, 53.3 % among patients of group 2, 72.4 % among patients of group 3 and 43.3 % - of the control group, however, it did not differ statistically significantly between groups (χ2=6,639, р=0,084) Conclusions: The unique window of implantation and the embryonic factor are among the main reasons for multiple failed implantation attempts. Personalization of the endometrial preparation protocol and preimplantation embryo diagnosis are effective methods to improve IVF outcomes

Debate 6: Microbiome Testing is Indicated for Implantation Failure in 2023

Motion: For Uninvestigated Recurrent Implantation Failure (RIF) has a significant cost, can waste embryos with the potential for life and leads to empirical therapies such as the use of steroids. Chronic Endometritis (CE) is a known cause of RIF is diagnosed by presence of plasma cells and worsens if steroids suppress the protective immune system response. Identifying plasma cells in endometrial tissue samples requires histological expertise, special staining and there is variation in numbers between tissue sections and microscope fields. Furthermore, culturing bacteria from low biomass environments like the endometrium is difficult and will not identify anaerobes and other fastidious organisms. The molecular technique of sequencing the 16S ribosome enables the identification of microbes that can create a hostile environment for embryos. There is clear evidence that some microbes and microbiome signatures are associated with RIF and that changing the microbiome is associated with higher implantation rates. There are established and emerging treatments for an aberrant microbiome that include antibiotic therapy, probiotics, faecal transplantation, and curettage. The more diagnostic information we can obtain to determine the cause of our patients RIF and then design specific, targeted treatments that are effective, the better their pregnancy outcomes will be. It is useful to test the microbiome and will only become more useful as this technology improves. Motion: Against The microbiome is closely related to women’s reproductive health, and therefore microbiome testing is becoming increasingly important in the field of reproductive medicine, especially in guiding assisted reproduction treatments such as infertility. The human microbiome is a collection of all microorganisms that exist on or within human tissues and fluids, as well as the corresponding anatomical sites where they are located, including the female reproductive tract, gastrointestinal tract, skin, semen, saliva, oral mucous membranes, etc., of which the ones that are most relevant to the study of female infertility mainly include the female reproductive tract flora and gastrointestinal tract flora. Several studies have shown that the composition of the microbiota in the female reproductive tract may affect embryo implantation and pregnancy success. An imbalanced or dysbiased microbiome of the female reproductive tract flora may lead to inflammation, altered immune responses, and hinder the optimal conditions needed for successful embryo implantation. Microbiome Testing can be accomplished through a variety of technologies, such as next-generation sequencing, which allows for a comprehensive analysis of microbial composition. Thus, microbiome testing that involves analyzing the microbial community in the female reproductive tract for imbalance or dysbiosis is a breakthrough point with great potential to aid in the treatment of recurrent implantation failure. For recurrent implantation failures, microbiome testing can help fertility specialists tailor a personalized treatment plan. By understanding an individual’s specific microbial profile, physicians can make informed decisions about potential interventions such as antibiotic therapy, probiotics, or other microbial modulation therapies. Of course, the use of microbiome testing should be carefully considered on a case-by-case basis and should be used in conjunction with other diagnostic tools and assessments to provide optimal treatment for patients with implantation failure.

Endometrial proteomic profile of patients with repeated implantation failure.

Successful embryo implantation, is the initiating step of pregnancy, relies on not only the high quality of the embryo but also the synergistic development of a healthy endometrium. Characterization and identification of biomarkers for the receptive endometrium is an effective method for increasing the probability of successful embryo implantation. Endometrial tissues from 22 women with a history of recurrent implantation failure (RIF) and 19 fertile controls were collected using biopsy catheters on 7-9 days after the peak of luteinizing hormone. Differentially expressed proteins (DEPs) were identified in six patients with RIF and six fertile controls using isobaric tag for relative and absolute quantitation (iTRAQ)-based proteomics analysis. Two hundred and sixty-three DEPs, including proteins with multiple bioactivities, such as protein translation, mitochondrial function, oxidoreductase activity, fatty acid and amino acid metabolism, were identified from iTRAQ. Four potential biomarkers for receptive endometrium named tubulin polymerization-promoting protein family member 3 TPPP3, S100 Calcium Binding Protein A13 (S100A13), 17b-hydroxysteroid dehydrogenase 2 (HSD17B2), and alpha-2-glycoprotein 1, zinc binding (AZGP1) were further verified using ProteinSimple Wes and immunohistochemical staining in all included samples (n=22 for RIF and n=19 for controls). Of the four proteins, the protein levels of TPPP3 and HSD17B2 were significantly downregulated in the endometrium of patients with RIF. Poor endometrial receptivity is considered the main reason for the decrease in pregnancy success rates in patients suffering from RIF. iTRAQ techniques based on isotope markers can identify and quantify low abundance proteomics, and may be suitable for identifying differentially expressed proteins in RIF. This study provides novel evidence that TPPP3 and HSD17B2 may be effective targets for the diagnosis and treatment of non-receptive endometrium and RIF.

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.

Expert consensus on diagnosis and treatment of recurrent implantation failure

Recurrent implantation failure (RIF) is a challenging clinical problem. Although in vitro fertilization-embryo transfer technology has made remarkable advances, RIF remains a significant obstacle to achieving a successful pregnancy. A unified criterion of diagnosis and treatment for RIF has yet to be created. The etiology of RIF is complicated, including maternal, male, and embryonic factors. Maternal factors include dysimmunity, prethrombotic state, poor endometrial receptivity, infection, anatomical abnormalities, and endocrine disorders. The complexity and diversity of etiologies of RIF require clinicians to individualize the strategy of diagnosis and treatment for RIF patients. This consensus will provide the most relevant evidence to date for the examination, evaluation, and management of RIF, provide a reference for clinicians to make decisions, and standardize the diagnosis and treatment of RIF.

Recurrent implantation failure: A comprehensive summary from etiology to treatment.

Implantation is the first step in human reproduction. Successful implantation depends on the crosstalk between embryo and endometrium. Recurrent implantation failure (RIF) is a clinical phenomenon characterized by a lack of implantation after the transfer of several embryos and disturbs approximately 10% couples undergoing in vitro fertilization and embryo transfer. Despite increasing literature on RIF, there is still no widely accepted definition or standard protocol for the diagnosis and treatment of RIF. Progress in predicting and preventing RIF has been hampered by a lack of widely accepted definitions. Most couples with RIF can become pregnant after clinical intervention. The prognosis for couples with RIF is related to maternal age. RIF can be caused by immunology, thrombophilias, endometrial receptivity, microbiome, anatomical abnormalities, male factors, and embryo aneuploidy. It is important to determine the most possible etiologies, and individualized treatment aimed at the primary cause seems to be an effective method for increasing the implantation rate. Couples with RIF require psychological support and appropriate clinical intervention. Further studies are required to evaluate diagnostic method and he effectiveness of each therapy, and guide clinical treatment.

Role of inflammatory factors in the etiology and treatment of recurrent implantation failure.

Recurrent implantation failure (RIF) is characterized by the absence of implantation after high-grade embryos are transferred to the endometrium by at least three in vitro fertilization cycles. It is one of the most important factors contributing to reproductive failure. After numerous barriers have been overcome to obtain good-quality embryos, RIF causes extreme distress and frustration in women and couples. In recent years, significant progress has been made in understanding how inflammatory factors, which include pro-inflammatory factors, anti-inflammatory factors, chemokines, and other molecules, contribute to RIF. Immunological abnormalities, hypercoagulability, and reproductive diseases are considered potential causes of RIF. In alloimmune disorders, inflammatory factors can affect the success rate of embryo implantation by altering T helper (Th)1/Th2 and Th17/regulatory T cell ratios and causing imbalances of uterine natural killer cells and macrophages. Autoimmune disorders can also lead to RIF. Inflammatory factors also play key roles in RIF-related disorders such as hypercoagulability, chronic endometritis, adenomyosis, hydrosalpinx, and endometriosis. This review focuses on the roles of inflammatory factors in RIF, including immune factors, blood hypercoagulable states, and reproductive diseases such as chronic endometritis, adenomyosis, hydrosalpinx, and endometriosis. It also summarizes the different treatments according to the causes of RIF and discusses the efficacy of sirolimus, peripheral blood mononuclear cells, low-dose aspirin combined with low-molecular-weight heparin, blocking interleukin-22, and gonadotropin-releasing hormone agonists in the treatment of RIF.

TOP2A deficit-induced abnormal decidualization leads to recurrent implantation failure via the NF-κB signaling pathway

BackgroundSuccessful implantation is a complex process that is influenced by embryo quality, endometrial receptivity, immune factors, and the specific type of in vitro fertilization protocol used. DNA topoisomerase IIα (TOP2A) is a well-known protein involved in cell proliferation; however, its expression and effect on the endometrium in recurrent implantation failure (RIF) have not been fully elucidated.MethodsThe human endometrial tissues of healthy controls and patients with RIF were collected. A proteomic analysis was performed to evaluate the differentially expressed proteins between the RIF group and the fertile control group. The expression patterns of TOP2A in the human preimplantation endometrium of the patients with RIF were determined by immunohistochemical staining, Western blotting and qRT-PCR. TOP2A knockdown (sh-TOP2A) T-HESCs were generated using lentiviruses. The expression of TOP2A in T-HESCs was manipulated to investigate its role in decidualization. The TOP2A-related changes in decidualization were screened by mRNA sequencing in decidualized TOP2A knockdown and control T-HESCs and then confirmed by Western blotting and immunofluorescence staining. TOP2A-deficient mice were generated by injection of TOP2A-interfering adenovirus on GD2.5 and GD3.5.ResultsWe performed a proteomic analysis of endometrial tissues to investigate the potential pathogenesis of RIF by comparing the patients with RIF and the matched controls and found that TOP2A might be a key protein in RIF. TOP2A is ubiquitously expressed in both stromal and glandular epithelial cells of the endometrium. The data indicate that TOP2A expression is significantly lower in the mid-secretory endometrium of women with RIF. TOP2A expression was downregulated under stimulation by 8-bromo-cAMP and MPA. Ablation of TOP2A resulted in upregulated expression of decidual biomarkers and morphological changes in the cells. Mechanistic analysis revealed that TOP2A regulates the NF-κB signaling pathway in decidualized T-HESCs. The TOP2A-deficient mice exhibited lower fetal weights.ConclusionsOur findings revealed that abnormal expression of TOP2A affects decidualization and changes the “window of implantation”, leading to RIF. TOP2A participates in the processes of decidualization and embryo implantation, functioning at least in part through the NF-κB pathway. Regulating the expression of TOP2A in the endometrium may become a new strategy for the prevention and treatment of RIF.

P-064 Clinical outcomes of 127 patients with recurrent implantation failure treated with testicular sperm aspiration (TESA)

Abstract Study question Are the embryological, clinical and newborn outcomes using aspirated testicular sperm improved in cases with recurrent implantation failure previously treated with ejaculated sperm? Summary answer Aspirated testicular sperm enabled to obtain significant higher embryological, clinical and newborn outcomes in cases with recurrent implantation failure previously treated with ejaculated sperm. What is known already High levels of sperm DNA fragmentation (SDF) were associated to poor clinical outcomes (1-Simon et al., 2017). Testicular sperm display lower SDF than ejaculated sperm (2-Sakas and Alvarez, 2010), improving clinical outcomes in cases with abnormal semen parameters (3-Awaga et al., 2018; 4-Kang et al., 2018), recurrent implantation failure (RIF) and pregnancy loss (RPL) (5-Esteves et al., 2017), and elevated SDF (6-Ambar et al., 2021). As only a few studies are specifically dedicated to RIF, we expanded the number of cases and first provided full demographic, stimulation, embryological, clinical and newborn outcomes. References 1-(https://doi.org/10.4103/1008-682X.182822); 2-(https://doi.org/10.1016/j.fertnstert.2009.10.046); 3-(https://doi.org/10.1016/j.rbmo.2018.08.017); 4-(https://doi.org/10.1038/s41598-018-26280-0); 5-(https://doi.org/10.1016/j.fertnstert.2017.06.018); 6-(https://doi.org/10.5534/wjmh.200084 Study design, size, duration We retrospectively evaluated during consecutive years (2010-2020) 63 patients with recurrent implantation failure, which accepted to perform testicular sperm aspiration (TESA) as an alternative treatment. These patients presented a long history of failed treatments (153 cycles) using ejaculated sperm. From these cycles, no pregnancy ensued. The present study compares 127 treatment cycles, 80 with testicular sperm (17 cases repeated TESA) and 47 with ejaculated sperm from the same patients performed at the present IVF clinic. Participants/materials, setting, methods Patients were screened for karyotype abnormalities, for Y-chromosome microdeletions (7-Gonçalves et al., 2016), and for SDF with the TUNEL assay (8-Sá et al., 2015). Conventional semen analysis was performed according to World Health Organization guidelines (9-WHO, 2010). Male evaluation and TESA was performed by the same experienced urologist (LF) according to established protocols (10-Madureira et al 2014). The procedure was performed entirely on an outpatient basis, with no complications reported. References 7-(https://doi.org/10.4103/1008-682X.172827); 8-(https://doi.org/10.1016/j.rbmo.2015.06.019); 9-(https://apps.who.int/iris/handle/10665/44261); 10-(https://doi.org/10.1111/j.2047-2927.2014.00231.x). Main results and the role of chance The mean ages were 35.5±3.4 (26-42)-female and 38.1±5.7 (29-59)-male. There were 4 abnormal karyotypes (3-female, 1-male), all without known relevance. Most cases had asthenozoospermia and teratozoospermia (65.1%), or oligoasthenoteratozoospermia (41.8%). Of the 19 cases with <5M/ml, none presented Y-chromosome microdeletions. Although we do not routinely perform SDF testing, 15 patients had previous SDF values (12, >20%; 8, >36%). Female basal characteristics and testicular evaluation were under normal values. The TESA procedure took about 15-20 min, and the time of laboratorial search around 30-60 min. Cases using testicular sperm showed significant higher rates of fertilization (64% vs 73%-p=0.005), blastocyst development (47% vs 62%-p=0.010), implantation (6% vs 27%-p=0.000), clinical pregnancy (10% vs 39%-p=0.001), live birth delivery (5% vs 28%-p=0.005) and newborn (5% vs 32%-p=0.000) than ejaculated sperm. No significant differences were observed regarding the rates of embryo cleavage (95% vs 94.8%) and high quality embryos (89.4% vs 94%), in the mean number of transferred embryos (1.8±0.4 vs 1.9±0.4), or in the abortion rate (2 cases-50% vs 7 cases-25.9%). Cases using testicular sperm had 22 frozen-thawed embryo transfer cycles, enabling per initiated cycle a cumulative pregnancy rate of 45%, live birth delivery rate of 31.3% and newborn rate of 37.5% (32 newborn). Limitations, reasons for caution Although presenting the higher number of cycles using TESA in the treatment of RIF, this number needs to be increased for drawing more definitive conclusions, as these women present a diversity of conditions, rendering subgrouping difficult. In the future, it would also be important to evaluate SDF in all cases. Wider implications of the findings In conclusion, the present results gave further evidence for the superiority of using testicular sperm instead of ejaculated sperm in cases with recurrent implantation failure. Data also evidences the security of using testicular sperm aspiration, as there were no pregnancy or delivery complications, or congenital anomalies among the 32 newborn. Trial registration number Not Applicable

O-022 A randomised controlled trial on Recurrent Implantation Failure treatment in a study model performed on women who failed egg donation cycles using GM-CSF (MOLGRAMOSTIM)

Abstract Study question Is the use of GM-CSF (molgramostim) effective in the treatment of recurrent implantation failure in egg donation cycles? Summary answer The clinical use of GM-CSF in women experienced implantation failure in egge donation cycles may be useful, What is known already The GM-CSF is a cytokine promoting leukocyte growth as well as trophoblast development. Recurrent implantation failure (RIF) is a clinical entity referring when implantation repeatedly failed to reach a stage recognizable by pelvic ultrasound in IVF cycles. There is no universally accepted definition for RIF. Several factors may determine implantation failure, such as maternal age, embyo aneuploidy, uterine anomalies. The efficacy of a specific treatment is difficult to test in this affection since embryos in general cases show an implantation rate of less than 50%. Study design, size, duration The study was conducted to the CERM-Hungaria, Rome, Italy, from the January 2020 to May 2021 on women with recurrent implantation failure after egg donation cycles. Inclusion criteria were: women, aged in between 35-49 years old underwent egg donation cycles with at least three previous transfers with good quality blastocysts that failed to reach pregnancy with no uterine defects (included adenomyosis), no systemic diseases. Participants/materials, setting, methods 50 women with recurrent implantation failure after egg donation cycles. Patients were randomly subdivided in two groups: one (25 women) treated with subcutaneous GM-CSF (Molgramostim) 0.3mg/kg/daily from the day before embryo transfer to the b-hcg day. The treatment was continued until the 8th week of gestation: the control group (25 women) was treated with subcutaneous saline solution infusion in the same way of the study group. Primary outcome was the ongoing pregnancy rate. Main results and the role of chance Epidemiological data of the two groups did not show statistically significant differences. The ongoing pregnancy rate in the group treated with GM-CSF was 84.0% (21/25) whereas in the control group was 44.0% (11/25), P < 0.0072. The absolute risk reduction was 40.0% (95%CI: 15.8%-64.2%). The NNT was 3.0 (95%CI: 1.6-6.3). Limitations, reasons for caution This study has a limited number of patients and more studies are needed to confirm these findings. Furthermore, recurrent implantation failure is a clinical entity difficult to classify and define, consequently to extrapolate a common indication for all patients with this should be carefully done. Wider implications of the findings The clinical use of GM-CSF in women experienced implantation failure may be an interesting treatment, if these data will confirmed, this treatment can be extended to all patients with recurrent implantation failure. Furthermore, the study model used may ba an interesting way to study recurrent implantation failure. Trial registration number NCT01718210

Increased expression of HOXA11-AS attenuates endometrial decidualization in recurrent implantation failure patients

Endometrial decidualization is a prerequisite for implantation, and impaired decidualization is associated with recurrent implantation failure (RIF). Coding genes of the HOX family have been clarified as critical regulators in endometrial decidualization, but the role of long non-coding RNAs (lncRNAs) in the HOX gene family has yet to be determined. The aim of this study was to clarify the possible roles of lncRNAs in the HOX gene family in decidualization. In this study, we identified that HOXA11-AS was the most reduced lncRNA in the HOX family in the human endometrium during the window of implantation, and it was elevated in RIF patients. Mechanistically, HOXA11-AS negatively regulated decidualization through competitive interaction with PTBP1, an RNA-binding protein. Binding of PTBP1 to HOXA11-AS limited PTBP1 availability to regulate PKM1/2 alternative splicing, resulting in enhanced PKM1 and diminished PKM2 expression, thus attenuating decidualization. The pattern of high HOXA11-AS expression and impaired PKM2 splicing was consistently observed in RIF patients. Collectively, our study indicates that the increase of HOXA11-AS is detrimental to endometrial decidualization, likely contributing to RIF. Our study may shed light on the pathogenesis and treatment of RIF.

Increased expression of HMGB1 in the implantation phase endometrium is related to recurrent implantation failure.

Impaired endometrial receptivity was the main cause of recurrent implantation failure (RIF); however, its underlying mechanisms had not been elucidated. This study aimed to determine the expression level of high-mobility group box protein 1 (HMGB1) in the endometrium with RIF and its effect on endometrial receptivity. Genome-wide expression profiling, real-time reverse transcription PCR, immunohistochemical staining, western blot, and in vitro assays were performed in this study. We found that HMGB1 expression was significantly decreased in the implantation phase endometrium in the control group (patients with tubal infertility and successfully achieve conception after the first embryo transfer) (P = 0.006). However, the expression levels of HMGB1 mRNA and protein were significantly upregulated during the implantation phase in endometrial tissues obtained from patients with RIF compared to that in the control group (P = 0.001), consistent with the results of the genome-wide expression profiling. Moreover, in vitro assays showed that increased expression of HMGB1 in human endometrial epithelial cells dramatically displayed a marked deficiency in supporting blastocysts and human embryonic JAR cells adhesion, which mimic the process of embryo adhesion. These findings strongly indicated that increased HMGB1 levels suppressed the epithelial cell adhesion capability, therefore contributing to impaired endometrial receptivity in patients with recurrent implantation failure, which can be used as a target for the recognition and treatment of recurrent implantation failure in clinical practice.

Hsa_circ_0038383-mediated competitive endogenous RNA network in recurrent implantation failure.

Background: Inadequate endometrial receptivity contributes to recurrent implantation failure (RIF) during IVF–embryo transfer. Though multiple circRNAs have been confirmed differentially expression in RIF, the potential function of novel circRNAs needed to be detected.Results: The top ten DEcircRNAs were selected as initial candidates. A ceRNA network was conducted on the basis of circRNA–miRNA–mRNA potential interaction, consisting of 10 DEcircRNAs, 28 DEmiRNAs and 59 DEmRNAs. Three down-regulation circRNAs with high degree of connectivity were verified by RT-qPCR, and results suggested that only hsa_circ_0038383 was significantly downregulation in RIF compared with control group. Subsequently, three hub genes (HOXA3, HOXA9 and PBX1) were identified as hub genes. Ultimately, a subnetwork was determined based on one DEcircRNA (hsa_circ_0038383), two DEmiRNAs (has-miR-196b-5p and has-miR-424-5p), and three DEmRNAs (HOXA3, HOXA9 and PBX1). Following verification, hsa_circ_0038383/miR-196b-5p/HOXA9 axis may be a key pathway in affecting RIF.Conclusion: In summary, a hsa_circ_0038383-mediated ceRNA network related to RIF was proposed. This network provided new insight into exploring potential biomarkers for diagnosis and clinical treatment of RIF.Methods: We retrieved the expression profiles of RIF from GEO databases (circRNA, microRNA and mRNA) and constructed a competing endogenous RNAs (ceRNA) network based on predicted circRNA–miRNA and miRNA–mRNA pairs. The expression levels of three hub DEcircRNAs identified by cytoscape were validated by RT-qPCR.

Definition, diagnostic and therapeutic options in recurrent implantation failure: an international survey of clinicians and embryologists.

What is the global variability in recurrent implantation failure (RIF) definition, investigation and therapy, currently offered to patients undergoing IVF? Definitions, diagnostic investigations and treatments offered to RIF patients differ widely amongst assisted reproduction healthcare professionals and clinical guidelines on RIF are urgently needed. RIF affects around 10% of patients undergoing IVF worldwide. There is no consensus on the definition of RIF, its diagnostic investigations or the therapeutic options, which leads to inconsistencies in clinical practice. A cross-sectional study of clinicians and embryologists was conducted between May and June 2020. The survey included 43 questions aimed at understanding participants' background and their current practice with regards to defining, investigating and managing RIF. The questions were designed by the European Society of Human Reproduction and Embryology (ESHRE) Special Interest Group (SIG) on implantation and early pregnancy following three consensus meetings. A total of 8579 ESHRE members from 6916 IVF centers were invited to participate using two global email calls based on their pre-specified interest in implantation and early pregnancy. SurveyMonkey and SPSS were used for data collection and analysis, respectively. Furthermore, differences were reported in the answers of European and non-European professionals, as well as between public and private settings and among clinicians clustered according to the average number of RIF patients treated per year. The final data set included 735 clinicians and 300 embryologist or IVF-biologists. The majority defines RIF based on the number of failed embryo transfers (ETs) with the most common threshold adopted being three ETs both fresh and frozen. More than two-thirds take lifestyle factors into account, mainly drugs, smoking and BMI. The highest consensus on which diagnostic investigations should be performed was reached for anatomical malformations and gynecological aspects focusing on hydrosalpinx, Asherman's syndrome, endometrial thickness and endometriosis. Concerning treatment of RIF patients, the highest consensus was reached for preconceptional therapies, including BMI adjustment, smoking and endometritis followed by therapies during IVF procedures. The response rate was relatively low, but comparable to other surveys. A consensus on definition, diagnosis and treatment of RIF would help to reduce costly, time-consuming and poorly validated approaches. No external funding was used. B.T. received support from Bayer for Clinical trials concerning endometriosis and Ferring for clinical trials concerning ovarian stimulation. She received reimbursement for travel expenses from Astropharm, Ferring. Dr Kade and is a shareholder of Reprognostics. She is a board member of the Austrian Society for Obstetrics and Gynecology (OEGGG), the associate head of the 'Reproduktionsmedizinische Zentren Baden-Württemberg' (RZBW), a member of guideline group of the German Society for Obstetrics and Gynecology (DGGG) and an editorial board member of the following journals: American Journal of Reproductive Immunology (AJRI), Archives of Gynecology and Obstetrics. All the other authors declare no conflict of interest. N/A.

The role of the serum exosomal and endometrial microRNAs in recurrent implantation failure

Objective It has been identified that endometrium specific microRNAs have different expression levels in endometrial tissues and maternal serum during endometrial cycle. The aim of this study was to analyze microRNA expression levels in recurrent implantation failure patients and healthy controls endometrial samples for enlightening the aetiopathogenesis of the disease. The second aim was to search for a potential noninvasive molecular biomarker in early diagnosis and treatment of Recurrent Implantation Failure (RIF) patients. Methods Endometrium and serum samples in two different phases (PP; proliferative phase and SP; secretory phase) from the same cases (RIF; n = 12 and Control; n = 8) were obtained. The expression levels of the microRNA by RT-qPCR method were measured. The expression levels of the healthy controls and study group were compared. Lastly performed target genes analysis of significantly dysregulated miRNA by target analyze databases for obtained related biological pathways. Results This study showed that has-miR-145, has-miR-23b, has-miR-31 and has-miR-30b were significantly up-regulated in PP and down-regulated in SP endometrium samples. In serum samples, has-miR-145 and hsa-miR-23b were significantly down-regulated in both of PP and SP. Target gene and pathway analysis for dysregulated miRNAs identified important, validated and predicted genes for the implantation process. Conclusions This study is the first study to obtain endometrium and serum samples in two different phases from the same cases and measure the candidate miRNAs expression. Our finding suggests that expression level of four candidate miRNAs may be involved in RIF development in women. Furthermore, these miRNAs can be potential biomarker for early diagnosis of RIF patients.

Intralipid Immunotherapy for Repeated IVF Failure

The intravenous fat emulsion, intralipid, has been hypothesised to be an effective and safe treatment for repeated in vitro fertilisation (IVF), implantation failure and pregnancy loss. This exploratory, retrospective cohort study determined pregnancy outcomes and documented adverse events associated with intralipid use. Ninety-three women were identified as having received intralipid for a history of repeated unsuccessful IVF cycles and pre-viable pregnancy loss in two Australian IVF units that independently recruited between October 2014 and July 2016. Pregnancy outcomes and adverse events were recorded in fresh and frozen embryo transfer cycles in which the infusion was administered. The 93 women who received intralipid had a clinical pregnancy rate of 40.0%, compared with 35.0% in 651 age-matched controls undergoing IVF, which was not significantly different. The intralipid group had a livebirth rate of 35.7%. Apart from flushing, which was experienced by one individual, there were no adverse events associated with intralipid use. As a prelude to definitive evidence of benefit, we did not identify a safety concern or reduced pregnancy rates in intralipid users compared to controls. Indeed, these outcomes were better than expected in a poor prognosis group. This data supports an argument for large, randomised controlled trials to determine the benefit of intralipid in the treatment of recurrent implantation failure or miscarriage.

Granulocyte colony-stimulating factor for intracytoplasmic sperm injection patients with repeated implantation failure: which route is best?†

The aim of this study was to assess whether the dual administration of granulocyte colony-stimulating factor (G-CSF) increases the effect of only systemic administration in patients with RIF. This retrospective study included 111 infertile normoresponder cases with two or more unsuccessful in vitro fertilisation/intracytoplasmic sperm injection (IVF/ICSI) treatments, despite the transfer of good quality embryos. Patients were divided into three groups according to using G-CSF and administration route; Group 1 included patients who received subcutaneous (SC) G-CSF only (n = 38), Group 2 comprised patients who received both intrauterine (IU) and SC G-CSF (n = 39), the control group included patients who did not receive G-CSF who were matched by age (n = 34). The IU route of G-CSF was employed on ovulation triggering day. G-CSF was administered via an IU insemination catheter. SC injection was started on the day of oocyte retrieval and administered for 15 days at 100,000 IU/kg. Foetal cardiac activity (clinical pregnancy) was present in 50 patients (46.2%) after embryo transfer, with 20 patients included in SC group (Group 1) (52.6%), 25 in SC + IU group (Group 2) (64.1%) and 8 (23.5%) in control group and significant difference was observed between groups (p: .001). Pregnancy resulted in live birth in 43 patients (39.8%), with 13 patients belonging in Group 1 (34.2%), 25 in Group 2 (61.5%) and 8 (23.5%) in control group; significant differences were observed between groups (p: .001). In conclusion, our results showed that dual administration of G-CSF was significantly more effective that the SC only method.Impact statementWhat is already known on this subject? A number of studies reported the possible benefits of granulocyte colony-stimulating factor (G-CSF) administration in recurrent implantation failure (RIF) and recurrent pregnancy loss patients; however, it is unclear which administration route is better.What do the results of this study add? Our results showed that G-CSF is a promising and safe agent for increasing live birth rates in patients with RIF. Additionally, dual administration is considered the better method than SC only administration.What are the implications of these findings for clinical practice and/or further research? Clinicians should consider a combination of IU use before ovulation triggering with SC administration starting from the day of oocyte collection for using G-CSF for the treatment of recurrent implantation failure. Additionally, our data show the need for research in the field of administration route of G-CSF for RIF. We suggest that further studies be performed in this field.

Systematic and standardized hysteroscopic endometrial injury for treatment of recurrent implantation failure.

To investigate the effect of hysteroscopic endometrial injury for treatment of recurrent implantation failure (RIF). This prospective and randomized controlled trial included 239 patients who had failed to achieve a clinical pregnancy after the transfer of at least four good-quality embryos in a minimum of three fresh or frozen-thawed embryo transfer cycles and were under the age of 40 years, who were randomized into two groups. The injury group (n=124) received endometrial injury during their hysteroscopic procedure, whereas the control group (n=115) did not. Patients who had endometrial pathologies were excluded from the study. There were no statistically significant differences in duration of gonadotrophin use (8.23 versus 8.30 days), total dose of gonadotrophins (2330 versus 2338IU), number of oocytes (7.03 versus 8.21), number of mature oocytes (5.27 versus 6.02), number of fertilized oocytes (4.19 versus 4.55), number of good-quality embryos (2.07 versus 2.43), number of embryos transferred (1.97 versus 1.93) or endometrial thickness (9.04 versus 9.35mm) between the injury group and control group, respectively. Clinical pregnancy rates (25.8% versus 15.6%, P=0.047), live birth rates (21.8% versus 12.2%, P=0.049) and implantation rates (14.2% versus 8.8%, P=0.036) were significantly different, favouring the injury group. This study suggests that endometrial injury is beneficial in RIF patients to increase the odds of implantation, clinical pregnancy and live birth.

Advances in the Treatment of Recurrent Implantation Failure

Recurrent implantation failure (RIF) is a syndrome of complex etiology. Excluding the involvement of embryonic factors, RIF is characterized by women aged ≤40 years who fail to achieve clinical pregnancy after at least four high-quality embryos transfer in a minimum of three fresh or frozen cycles. However, current methods in the treatment of RIF are controversial. So far, there are no reports of any criteria or guidelines, and the mechanism of RIF is still not clear. Herein, we summarize the pathogenesis of RIF and highlight recent methods in its treatment, to provide reference for the basic and clinical research on RIF.

Introduction to special issue on implantation

Introduction to special issue on implantation