Does antibiotic therapy for chronic endometritis improve clinical outcomes of patients with recurrent implantation failure in subsequent IVF cycles? A systematic review and meta-analysis

Variation in diagnostic methods, criteria, and treatment for chronic endometritis: A nationwide survey in Japan

AIM

To investigate variation in the diagnosis and treatment of chronic endometritis (CE) at the national level in Japan.

METHODS

We performed a nationwide survey targeting all assisted reproductive technology (ART) facilities across Japan between 2021 and 2022. Diagnostic methods, criteria, and first- and second-line treatment protocols for CE were collected via a questionnaire.

RESULTS

Among 616 ART facilities, 437 responded to the survey (response rate: 70.9%) of which 339 (77.6%) implemented diagnosis and treatment of CE. In the diagnosis of CE, 214 (63.1%) facilities used CD138 immunohistochemical staining of endometrial tissue, while hysteroscopy was the most frequently used as an adjunct diagnostic method (241 facilities, 71.1%). The most frequent cutoff value of CD138-positive cells for diagnosing CE was 3-5 cells/20 high-power fields (50%), but 7.9% (17 facilities) and 5.1% (11 facilities) used cutoff values of 1 and 2 cells, respectively. The most common first- and second-line treatment methods were doxycycline (210 facilities, 61.9%) and ciprofloxacin + metronidazole (164 facilities, 48.0%), respectively.

CONCLUSIONS

There is considerable variation in the number of CD138-positive cells used for diagnosing CE. Establishing unified diagnostic criteria and therapeutic methods for CE is essential to provide standardized medicine for CE at the national level.

If CE affects infertile women's outcomes after surgery?

OBJECTIVE

To investigate the prevalence of chronic endometritis (CE) in infertile patients and whether it affects spontaneous pregnancy after reproductive surgery in infertile patients.

MATERIALS AND METHODS

In this study, we collected clinical information on infertility patients who underwent reproductive surgery at the Reproductive Medicine Centre of the Second Hospital of Lanzhou University from 2021.1 to 2022.8. All patients underwent laparoscopic and hysteroscopic surgery. Tubal lubrication was performed concurrently with endometrial sample collection and pathological examination. The specimens were immunohistochemically stained with CD38 and CD138, and those who tested positive at the same time were diagnosed with chronic endometritis. As of 2023.9, the patients were followed up by telephone to determine whether chronic endometritis impacted postoperative pregnancy.

OUTCOME

A total of 81 patients were finally included in the study. Of these, 25 were in the chronic endometritis group, and 56 were in the non-chronic endometritis group. There were no appreciable differences between the two groups' demographic statistics. Furthermore, neither the bilateral appendages nor the uterus's intraoperative conditions showed a statistically significant difference. Patients in the chronic endometritis group had a longer time to conception from the time of surgery (7 (6.00-11.75) vs. 10 (6.50-16.00), p = 0.467) and a lower rate of spontaneous pregnancies (8/25 = 32.00 % vs. 28/55 = 50.00 %, p = 0.132) than patients with non-chronic endometritis. Among the patients who had successful spontaneous pregnancies after surgery, approximately 77.14 % had live births and 22.86 % had miscarriages, and the live birth rate between the two groups was not significantly different. (21/28 = 75.00 % vs 7/8 = 87.50 %, p = 0.651) CONCLUSION: Chronic endometritis affects approximately 31.82% of infertile patients, and following reproductive surgery, it has no discernible impact on spontaneous pregnancy.

Bridging the Diagnostic Gap between Histopathologic and Hysteroscopic Chronic Endometritis with Deep Learning Models

Chronic endometritis (CE) is an inflammatory pathologic condition of the uterine mucosa characterized by unusual infiltration of CD138(+) endometrial stromal plasmacytes (ESPCs). CE is often identified in infertile women with unexplained etiology, tubal factors, endometriosis, repeated implantation failure, and recurrent pregnancy loss. Diagnosis of CE has traditionally relied on endometrial biopsy and histopathologic/immunohistochemistrical detection of ESPCs. Endometrial biopsy, however, is a somewhat painful procedure for the subjects and does not allow us to grasp the whole picture of this mucosal tissue. Meanwhile, fluid hysteroscopy has been recently adopted as a less-invasive diagnostic modality for CE. We launched the ARCHIPELAGO (ARChival Hysteroscopic Image-based Prediction for histopathologic chronic Endometritis in infertile women using deep LeArninG mOdel) study to construct the hysteroscopic CE finding-based prediction tools for histopathologic CE. The development of these deep learning-based novel models and computer-aided detection/diagnosis systems potentially benefits infertile women suffering from this elusive disease.

Antibiotic cured chronic endometritis remains a risk factor for early pregnancy loss in the subsequent frozen euploid embryo transfer

RESEARCH QUESTION

Do patients with antibiotic-cured chronic endometritis (CCE) have a comparable pregnancy outcome to those with non-chronic endometritis (NCE) in the subsequent frozen embryo transfer (FET) cycle?

DESIGN

A retrospective cohort analysis included 833 patients in their first FET cycles with single euploid embryo transfer. Chronic endometritis (≥5 CD138+ plasma cells per high-power field [CD138+/HPF]) was treated with standard antibiotic therapy. Patients were classified into two groups: the NCE group (n = 611, <5 CD138+/HPF) and the CCE group (n = 222, ≥5 CD138+/HPF and cured after antibiotic treatment). Pregnancy outcomes were compared. NCE group was divided into subgroup 1 (CD138+/HPF = 0) and subgroup 2 (CD138+/HPF = 1-4) for further analysis.

RESULTS

The rate of early pregnancy loss (EPL), incorporating all losses before 10 weeks' gestation, was significantly higher in the CCE group than the NCE group (21.2% versus 14.2%, P = 0.016), and the difference was statistically significant (adjusted odds ratio [AOR] 1.68, 95% confidence interval [CI] 1.11-2.55). No significant differences were observed between the two groups with regard to other pregnancy outcomes. In the subgroup analysis, the EPL rate and biochemical pregnancy rate were significantly higher in subgroup 2 than subgroup 1 (17.2% versus 9.4%, AOR 2.21, 95% CI 1.30-3.74; 12.2% versus 6.9%, AOR 2.01, 95% CI 1.09-3.68).

CONCLUSIONS

Chronic endometritis cured by standard antibiotic therapy remains a risk factor for EPL in FET cycles, although no differences were found in live birth rates between patients with CCE or with NCE.

Current perspectives on endometrial receptivity: A comprehensive overview of etiology and treatment

Recurrent implantation failure (RIF) remains a challenging problem in assisted reproductive technology (ART). Further insights into uterine abnormalities that can disturb embryo implantation should be obtained. This review provides an overview of the effects of organic and non-organic uterine disorders on endometrial receptivity. The results suggest that various uterine pathologies can lead to defective embryo implantation via multiple mechanisms. In particular, uterine adenomyosis dysregulates molecular and cellular interactions that are vital for successful embryo implantation with a background of chronic inflammation, which may be alleviated by pretreatment with a gonadotropin-releasing hormone agonist. Uterine myomas can cause endometrial deformation and adverse alterations in uterine contractility. Nonetheless, the effectiveness of myomectomy remains debated, and endometrial polyp removal may be considered, particularly in patients with RIF. Chronic endometritis abrogates the appropriate uterine immunological environment critical for embryo implantation. Abnormal endometrial microbiota have been suggested to influence endometrial receptivity; however, supporting evidence is currently scarce. Platelet-rich plasma therapy may be a potential treatment for thin endometria; nevertheless, further validation is required. Endometrial receptivity analysis can detect dysregulation of the window of implantation, and new non-invasive methods for predicting endometrial receptivity have recently been proposed. However, numerous issues still need to be fully clarified. Further clinical and basic studies are necessary to investigate the pathophysiology of defective endometrial receptivity and identify optimal treatments for patients undergoing ART, especially those with RIF.

Combined oral antibiotics and intrauterine perfusion can improve in vitro fertilization and embryo transfer pregnancy outcomes in patients with chronic endometritis and repeated embryo implantation failure

BACKGROUND

The aim of this retrospective study was to investigate whether oral antibiotics (doxycycline and metronidazole) combined with intrauterine perfusion (gentamicin and dexamethasone) are beneficial for patients with repeated implantation failure (RIF) and chronic endometritis (CE) to improve clinical pregnancy outcomes.

METHODS

Patients with RIF and CE were diagnosed using hysteroscopy and histology together. A total of 42 patients were enrolled in the study. All patients received oral antibiotics (doxycycline combined with metronidazole) and 22 patients underwent intrauterine perfusion (gentamicin combined with dexamethasone) immediately after the end of oral antibiotic therapy. Pregnancy outcomes were evaluated during the first in vitro fertilization (IVF) and embryo transfer (ET) cycle.

RESULTS

For the first D3 ET after treatment with oral antibiotics (doxycycline and metronidazole) combined with intrauterine perfusion (gentamicin and dexamethasone), higher embryo implantation rate (30.95% vs. 26.67%, P = 0.0308), clinical pregnancy rate (30% vs. 50%, P < 0.001), live birth rate (33.33% vs. 45.45%, P < 0.0001). No fetal malformations or ectopic pregnancies were observed.

CONCLUSION

We report oral antibiotics (doxycycline and metronidazole) combined with intrauterine perfusion (gentamicin and dexamethasone) as a novel treatment for CE to improve the outcomes of successful pregnancy compared with those of oral antibiotics alone.

ESHRE good practice recommendations on recurrent implantation failure

STUDY QUESTION

How should recurrent implantation failure (RIF) in patients undergoing ART be defined and managed?

SUMMARY ANSWER

This is the first ESHRE good practice recommendations paper providing a definition for RIF together with recommendations on how to investigate causes and contributing factors, and how to improve the chances of a pregnancy.

WHAT IS KNOWN ALREADY

RIF is a challenge in the ART clinic, with a multitude of investigations and interventions offered and applied in clinical practice, often without biological rationale or with unequivocal evidence of benefit.

STUDY DESIGN SIZE DURATION

This document was developed according to a predefined methodology for ESHRE good practice recommendations. Recommendations are supported by data from the literature, if available, and the results of a previously published survey on clinical practice in RIF and the expertise of the working group. A literature search was performed in PubMed and Cochrane focussing on 'recurrent reproductive failure', 'recurrent implantation failure', and 'repeated implantation failure'.

PARTICIPANTS/MATERIALS SETTING METHODS

The ESHRE Working Group on Recurrent Implantation Failure included eight members representing the ESHRE Special Interest Groups for Implantation and Early Pregnancy, Reproductive Endocrinology, and Embryology, with an independent chair and an expert in statistics. The recommendations for clinical practice were formulated based on the expert opinion of the working group, while taking into consideration the published data and results of the survey on uptake in clinical practice. The draft document was then open to ESHRE members for online peer review and was revised in light of the comments received.

MAIN RESULTS AND THE ROLE OF CHANCE

The working group recommends considering RIF as a secondary phenomenon of ART, as it can only be observed in patients undergoing IVF, and that the following description of RIF be adopted: 'RIF describes the scenario in which the transfer of embryos considered to be viable has failed to result in a positive pregnancy test sufficiently often in a specific patient to warrant consideration of further investigations and/or interventions'. It was agreed that the recommended threshold for the cumulative predicted chance of implantation to identify RIF for the purposes of initiating further investigation is 60%. When a couple have not had a successful implantation by a certain number of embryo transfers and the cumulative predicted chance of implantation associated with that number is greater than 60%, then they should be counselled on further investigation and/or treatment options. This term defines clinical RIF for which further actions should be considered. Nineteen recommendations were formulated on investigations when RIF is suspected, and 13 on interventions. Recommendations were colour-coded based on whether the investigations/interventions were recommended (green), to be considered (orange), or not recommended, i.e. not to be offered routinely (red).

LIMITATIONS REASONS FOR CAUTION

While awaiting the results of further studies and trials, the ESHRE Working Group on Recurrent Implantation Failure recommends identifying RIF based on the chance of successful implantation for the individual patient or couple and to restrict investigations and treatments to those supported by a clear rationale and data indicating their likely benefit.

WIDER IMPLICATIONS OF THE FINDINGS

This article provides not only good practice advice but also highlights the investigations and interventions that need further research. This research, when well-conducted, will be key to making progress in the clinical management of RIF.

STUDY FUNDING/COMPETING INTERESTS

The meetings and technical support for this project were funded by ESHRE. N.M. declared consulting fees from ArtPRED (The Netherlands) and Freya Biosciences (Denmark); Honoraria for lectures from Gedeon Richter, Merck, Abbott, and IBSA; being co-founder of Verso Biosense. He is Co-Chief Editor of Reproductive Biomedicine Online (RBMO). D.C. declared being an Associate Editor of Human Reproduction Update, and declared honoraria for lectures from Merck, Organon, IBSA, and Fairtility; support for attending meetings from Cooper Surgical, Fujifilm Irvine Scientific. G.G. declared that he or his institution received financial or non-financial support for research, lectures, workshops, advisory roles, or travelling from Ferring, Merck, Gedeon-Richter, PregLem, Abbott, Vifor, Organon, MSD, Coopersurgical, ObsEVA, and ReprodWissen. He is an Editor of the journals Archives of Obstetrics and Gynecology and Reproductive Biomedicine Online, and Editor in Chief of Journal Gynäkologische Endokrinologie. He is involved in guideline developments and quality control on national and international level. G.L. declared he or his institution received honoraria for lectures from Merck, Ferring, Vianex/Organon, and MSD. He is an Associate Editor of Human Reproduction Update, immediate past Coordinator of Special Interest Group for Reproductive Endocrinology of ESHRE and has been involved in Guideline Development Groups of ESHRE and national fertility authorities. D.J.M. declared being an Associate Editor for Human Reproduction Open and statistical Advisor for Reproductive Biomedicine Online. B.T. declared being shareholder of Reprognostics and she or her institution received financial or non-financial support for research, clinical trials, lectures, workshops, advisory roles or travelling from support for attending meetings from Ferring, MSD, Exeltis, Merck Serono, Bayer, Teva, Theramex and Novartis, Astropharm, Ferring. The other authors had nothing to disclose.

DISCLAIMER

This Good Practice Recommendations (GPR) document represents the views of ESHRE, which are the result of consensus between the relevant ESHRE stakeholders and are based on the scientific evidence available at the time of preparation. ESHRE GPRs should be used for information and educational purposes. They should not be interpreted as setting a standard of care or be deemed inclusive of all proper methods of care, or be exclusive of other methods of care reasonably directed to obtaining the same results. They do not replace the need for application of clinical judgement to each individual presentation, or variations based on locality and facility type. Furthermore, ESHRE GPRs do not constitute or imply the endorsement, or favouring, of any of the included technologies by ESHRE.

Deoxycholic acid inhibits Staphylococcus aureus-induced endometritis through regulating TGR5/PKA/NF-κB signaling pathway

Endometritis, a common gynecological disease, is the most common cause of infertility. As a natural metabolite of gut microbiota, deoxycholic acid (DCA) has been reported to have anti-inflammatory function. In the current study, the protective role of DCA on Staphylococcus aureus (S.aureus)-induced endometritis was tested. In vivo, DCA inhibited uterine histological change, MPO activity, endometrial barrier disruption, and inflammatory cytokine production induced by S.aureus. In vitro, DCA suppressed S.aureus-induced TNF-α and IL-1ß production in mouse endometrial epithelial cells (mEECs). Also, DCA markedly suppressed S.aureus-induced NF-κB activation. Takeda G protein-coupled receptor 5 (TGR5)is a critical bile acid membranereceptor that mainly regulated the cyclic AMP (cAMP)/protein kinase A (PKA)signaling pathway to inhibit NF-κB activation. We found DCA significantly increased TGR5 and PKA expression and S.aureus-induced inflammatory cytokine production and NF-κB activation were prevented by TGR5 inhibitor and PKA inhibitor. In conclusion, DCA protected S.aureus-induced endometritis by regulating TGR5/PKA/NF-κB signaling pathway.

Precision Medicine for Chronic Endometritis: Computer-Aided Diagnosis Using Deep Learning Model

Chronic endometritis (CE) is a localized mucosal infectious and inflammatory disorder marked by infiltration of CD138(+) endometrial stromal plasmacytes (ESPC). CE is drawing interest in the field of reproductive medicine because of its association with female infertility of unknown etiology, endometriosis, repeated implantation failure, recurrent pregnancy loss, and multiple maternal/newborn complications. The diagnosis of CE has long relied on somewhat painful endometrial biopsy and histopathologic examinations combined with immunohistochemistry for CD138 (IHC-CD138). With IHC-CD138 only, CE may be potentially over-diagnosed by misidentification of endometrial epithelial cells, which constitutively express CD138, as ESPCs. Fluid hysteroscopy is emerging as an alternative, less-invasive diagnostic tool that can visualize the whole uterine cavity in real-time and enables the detection of several unique mucosal findings associated with CE. The biases in the hysteroscopic diagnosis of CE; however, are the inter-observer and intra-observer disagreements on the interpretation of the endoscopic findings. Additionally, due to the variances in the study designs and adopted diagnostic criteria, there exists some dissociation in the histopathologic and hysteroscopic diagnosis of CE among researchers. To address these questions, novel dual immunohistochemistry for CD138 and another plasmacyte marker multiple myeloma oncogene 1 are currently being tested. Furthermore, computer-aided diagnosis using a deep learning model is being developed for more accurate detection of ESPCs. These approaches have the potential to contribute to the reduction in human errors and biases, the improvement of the diagnostic performance of CE, and the establishment of unified diagnostic criteria and standardized clinical guidelines for the disease.

Challenges in Clinical Diagnosis and Management of Chronic Endometritis

Chronic endometritis (CE) is a local mucosal infectious and inflammatory disorder characterized by unusual filtration of CD138(+) endometrial stromal plasmacytes. CE is attracting attention due to its potential association with infertility of unknown etiology, repeated implantation failure, recurrent pregnancy loss, and several maternal/neonatal complications. Due to the variance in study design among researchers, universal diagnostic criteria remain to be established for the clinical diagnosis and management of CE. This review article aims to summarize current knowledge and provide insights into unsolved questions on CE to establish clinical guidelines for the disease from the viewpoint of human reproduction.