Review: Chronic endometritis and its effect on reproduction

Exosomes secreted from adipose-derived stem cells inhibit M1 macrophage polarization ameliorate chronic endometritis by regulating SIRT2/NLRP3

Chronic endometritis (CE) is a key factor in adverse pregnancy outcomes such as miscarriage and infertility. Macrophages are an important immune cell type that secrete pro-inflammatory and anti-inflammatory cytokines that are essential for maintaining endometrial function. This study aimed to investigate the key mechanisms by which exosomes derived from adipose-derived mesenchymal stem cells (ADSCs) regulate macrophage polarization through the sirtuin 2 (SIRT2)/NOD-like receptor pyrin containing 3 (NLRP3) axis and exert a protective effect on CE. Exosomes were obtained from ADSCs (ADSCs-exo) using the classical ultracentrifugation method and characterized using transmission electron microscopy, nanoparticle tracking analysis, and western blotting. ADSCs-exo protective effects on CE mice and RAW 264.7 cells and its related molecular mechanisms were investigated using real-time quantitative polymerase chain reaction, western blotting, enzyme-linked immunosorbent assay, flow cytometry, immunofluorescence, immunoprecipitation, hematoxylin and eosin staining, and immunohistochemistry. ADSCs-exo significantly inhibited M1 macrophage polarization, as evidenced by a 54% reduction in tumor necrosis factor alfa (TNF-α), a 46% reduction in interleukin 1β (IL-1β), and a 36% reduction in interleukin 6 (IL-6) levels in LPS-induced RAW264.7 cells. In vivo, ADSCs-exo treatment reduced the expression of TNF-α by 50%, IL-1β by 58%, and IL-6 by 49% in the uterine tissues of CE mice. Moreover, ADSCs-exo upregulated the expression of SIRT2, promoted the deacetylation modification of NLRP3 to inhibit NLRP3 inflammasome activation, and further suppressed M1 macrophage polarization. However, these trends were reversed after SIRT2 silencing. Our experimental results demonstrate that ADSCs-exo alleviate CE by regulating the SIRT2/NLRP3 axis to inhibit M1 macrophage polarization. This provides a potential theoretical basis for the therapeutic role of stem cells in CE.

The risk factors and prognostic impact of different benign pathologic types of background endometrium surrounding endometrial polyps

OBJECTIVE

This retrospective study investigated the prognostic significance and risk factors of benign pathologic types of background endometrium surrounding endometrial polyps (EPs).

METHODS

We assessed 206 patients who underwent hysteroscopic polypectomy and background endometrium biopsy. Patients were categorized into four groups based on the pathologic types of background endometrium: normal proliferative endometrium (NPE), polypoid hyperplastic endometrium (PHE), chronic endometritis (CE), and non-atypical endometrial hyperplasia (NEH). We employed univariable comparisons and multivariable logistic regression analysis to identify risk factors of PHE, CE, and NEH compared to NPE. Abnormal uterine bleeding (AUB) and recurrence of EPs were monitored over a 12-month postoperative follow-up period.

RESULTS

Independent risk factors for EPs with a background of CE included a history of genital tract infection (OR = 8.88, 95% CI: 2.95-26.70, P = 0.000), adenomyosis (OR = 13.70, 95% CI: 3.38-55.52, P = 0.000), and hydrosalpinx (OR = 2.23, 95% CI: 1.59-54.09, P = 0.013). Age (OR = 1.18, 95% CI: 1.07-1.30, P = 0.001) and BMI (OR = 1.33, 95% CI: 1.11-1.61, P = 0.003) were significant risk factors for EPs with a background of NEH. Patients with PHE had higher recurrence rates of EPs following 12 months of follow-up. Moreover, background endometrium types PHE, CE, and NEH were associated with poorer control of AUB.

CONCLUSION

Our study underscores the importance of examining the histopathologic characteristics of the background endometrium surrounding EPs, as these benign lesions significantly influence the recurrence and symptomatology of EPs.

Fucoxanthin attenuates LPS-induced endometritis via inhibiting inflammatory factors through the NF-κB pathway

Endometritis is an infectious disease of the female reproductive system and commonly treated with antibiotics. However, the high resistance rates to antibiotics necessitate the urgent research for new and effective therapeutic strategies. The aim of this research is to explore the effect of fucoxanthin (FX) on endometritis through in vitro and in vivo assays. The effect of FX on inflammation was first explored in vitro using LPS-induced bovine endometrial epithelial (BEND) cell injury model. After the anti-inflammation effect of FX was confirmed in vitro, the effect of FX on endometritis was investigated in vivo using LPS-induced mice model. The female mice were randomly assigned into control, control + FX, LPS, and LPS + FX (100, 200 mg/kg) groups. The histological features of the uterus and expression levels of NF-κBp65 and inflammatory mediators (COX-2, iNOS, IL-1β, IL-6, and TNF-α) in the uterine tissue were compared among the animal groups. Our in vitro results showed that LPS induced BEND cell damage while significantly enhancing the expression of NF-κBp65 and inflammatory mediators (COX-2, iNOS, IL-1β, IL-6, and TNF-α). Nevertheless, pretreatment with FX reversed the abnormal phenomena caused by LPS. In vivo, LPS treatment resulted in obvious histopathological uterus damages, which were alleviated by FX treatment. Consistent with the in vitro assay, FX treatment also inhibited the expression of NF-κBp65 and inflammatory mediators in the animal experiments. Our study implies that FX is a potential therapeutic agent for endometritis. The beneficial function of FX on endometritis was achieved by inhibiting the inflammatory factors through the NF-κB pathway.

Comparing the accuracy of Pipelle versus hysteroscopy and curettage in the diagnosis of chronic endometritis in women with recurrent implantation failure: A prospective cross-sectional study

OBJECTIVES

Chronic endometritis (CE) is defined as chronic inflammation in the endometrium; when treated, implantations significantly improve. The standard test for CE confirmation is an endometrial biopsy, but the appropriate sampling method needs to be clarified. We conducted this study to compare pipelle biopsy and hysteroscopy with curettage.

STUDY DESIGN

This is a prospective cross-sectional study with all (40 patients) RIF patients under 40 referred to our tertiary center between December 2021, and December 2022 who underwent pipelle biopsy and hysteroscopy with curettage between days twelve to fifteen of their menstruation cycle. We then compared the diagnostic accuracy, demographics, and previous IVF history between the CE and non-CE groups.

RESULTS

Patients had a mean age of 34 ( ± 5.4) years and BMI of 25.8 ( ± 3.6). Thirteen patients (32.5%) were diagnosed with CE. There was no significant difference between CE and non-CE groups regarding maternal or paternal age, BMI, number of IVFs and embryos, and interval from the last IVF. Pipelle biopsy had 100% accuracy for CE diagnosis, while hysteroscopy with curettage had a sensitivity of 92.3% (95% CI: 77.8% - 100%) and specificity of 100%. Based on McNemar's test, the two sampling methods had no significant difference (P = 1.0 and 0.317, respectively).

CONCLUSION

There is no significant difference between the two methods in the diagnosis accuracy of CE in RIF patients. Since pipelle is more cost-effective and has fewer complications than hysteroscopy with curettage, pipelle biopsy may replace curettage for CE diagnosis.

Extracellular vesicles in endometrial-related diseases: role, potential and challenges

Endometrial dysfunction underlies many common gynecologic disorders, such as endometriosis, endometrial cancer, intrauterine adhesions, and endometritis, which affect many women around the world. Extracellular vesicles play an important role in the pathophysiologic process of endometrial-related diseases. Extracellular vesicles are released by cells, which usually act as a form of intercellular communication, affecting biological processes such as fibrosis, angiogenesis, cell proliferation, and inflammatory responses by transferring their own proteins, lipids, RNA transcripts, and DNA for messaging, and play a key role in physiological dynamic homeostasis and disease development. This review combines the studies of the last decade, using the sub-description method to introduce the application of different sources of extracellular vesicles in the diagnosis and treatment of related diseases, and discusses the challenges faced by extracellular vesicles in the diagnostic and therapeutic application of endometriosis-related diseases, with the aim of contributing to our understanding of the mechanism of action of extracellular vesicles and their therapeutic roles, so as to provide a reference for the development of endometriosis-related diseases, as well as their prognosis and treatment.

Pelvic peritoneal endometriosis is linked to the endometrial inflammatory profile: a prospective cohort study

BACKGROUND

Pelvic endometriosis is an estrogen-driven inflammatory syndrome of unknown origin that alters the peritoneal microenvironment and likely impairs endometrial receptivity, adversely affecting fertility. Chronic endometritis (CE) may be a potential contributing factor to reduced endometrial receptivity in endometriosis. The aim of the study was to analyze the correlation between pelvic endometriosis and CE.

METHODS

The study included women undergoing laparoscopy for suspected pelvic endometriosis, and each underwent endometrial aspiration biopsy for CE. The stage of endometriosis was assessed intraoperatively, and CE activity was evaluated histopathologically and immunohistochemically. The associations between selected clinical characteristics of the disease and the density of endometrial plasma cells, immunohistochemical status, and histopathological profile of the endometrium were analyzed.

RESULTS

Stage III endometriosis reduced the risk of the inflammatory immunohistochemical profile by 80% (OR = 0.18, p = 0.037) when compared to Stage I. Peritoneal endometriosis was associated with a 3.429-fold increase in the risk of the immunohistochemical endometrial inflammatory profile (OR = 3.429, p = 0.038). No significant associations were found between the clinical features of the disease and plasma cell density or the histopathological profile of the endometrium (all p values > 0.05). No significant differences were observed in IVF use (p = 0.67), pregnancy rates (p = 1), or live birth rates (p = 0.41) between infertile women with and without CE.

CONCLUSIONS

Should peritoneal endometriosis be diagnosed during a laparoscopy conducted for the treatment of infertility, it is advisable to obtain an endometrial biopsy for CE evaluation, as this may enhance the efficacy of the therapeutic approach. The hypothetical link between pelvic endometriosis-related inflammation, its clinical manifestations, and CE requires further investigation. The lack of a noninvasive marker for endometriosis and its grade limits the study results due to reliance on surgical cases, highlighting the need for advanced research in the field of noninvasive diagnostic tools.

TRIAL REGISTRATION

NCT05824507 (registered April 20, 2023).

Uterine Microbiota and Bisphenols: Novel Influencers in Reproductive Health

Infertility affects 8-12% of couples worldwide, and 30-75% of preclinical pregnancy losses are due to a failure during the implantation process. Exposure to endocrine disruptors, like bisphenols, among others, has been associated with the increase in infertility observed in the past decades. An increase in infertility has correlated with exposure to endocrine disruptors like bisphenols. The uterus harbors its own microbiota, and changes in this microbiota have been linked to several gynecological conditions, including reproductive failure. There are no studies on the effects of bisphenols on the uterine-microbiota composition, but some inferences can be gleaned by looking at the gut. Bisphenols can alter the gut microbiota, and the molecular mechanism by which gut microbiota regulates intestinal permeability involves Toll-like receptors (TLRs) and tight junction (TJ) proteins. TJs participate in embryo implantation in the uterus, but bisphenol exposure disrupts the expression and localization of TJ proteins. The aim of this review is to summarize the current knowledge on the microbiota of the female reproductive tract (FRT), its association with different reproductive diseases-particularly reproductive failure-the effects of bisphenols on microbiota composition and reproductive health, and the molecular mechanisms regulating uterine-microbiota interactions crucial for embryo implantation. This review also highlights existing knowledge gaps and outlines research needs for future risk assessments regarding the effects of bisphenols on reproduction.

Advancements in Hysteroscopic Diagnosis and Management of Endometritis

Infertility remains a complex clinical challenge, with intrauterine pathologies contributing to a significant percentage of in vitro fertilization (IVF) failures. Chronic endometritis (CE) has gained attention due to its potential association with unexplained infertility and recurrent miscarriage. This review explores the role of hysteroscopy in diagnosing and treating CE. The endometrium undergoes dynamic changes orchestrated by ovarian steroids, and disturbances may lead to CE, characterized by plasma cell infiltration. Diagnosis traditionally relies on histopathologic examination, but hysteroscopy offers real-time imaging, revealing the specific macroscopic alterations associated with CE. However, diagnostic accuracy varies, prompting the need for standardized criteria. CE has been linked to poor reproductive outcomes, emphasizing the importance of effective treatment. Antibiotic therapy is a common approach, with doxycycline as the first-line regimen. Hysteroscopic polypectomy, targeting non-infectious CE, emerges as a promising treatment, demonstrating fertility benefits. The review underscores the significance of hysteroscopy in diagnosing and treating CE, providing insights into its impact on reproductive outcomes in infertile women. Further prospective studies are needed to validate these findings and establish unified diagnostic criteria.

Chronic Endometritis and Antimicrobial Resistance: Towards a Multidrug-Resistant Endometritis? An Expert Opinion

Chronic endometritis (CE) is a persistent inflammatory condition of the endometrium characterized by abnormal infiltration of plasma cells into the endometrial stroma. Frequently associated with repeated implantation failure, recurrent pregnancy loss, and infertility, CE significantly impacts women's health, contributing to conditions such as abnormal uterine bleeding and endometriosis. Treatment typically involves antibiotic therapy; however, the efficacy of these treatments is increasingly compromised by the rise of antimicrobial resistance (AMR). This paper examines the critical links between AMR and CE, proposing strategies to enhance clinical management and optimize treatment outcomes.

The correlation between chronic endometritis and Caesarean scar diverticulum

PURPOSE

To investigate the risk factors for Caesarean Scar Diverticulum (CSD) with Chronic Endometritis (CE) and the correlation between CE and clinical symptoms of CSD.

METHODS

The frequency of CE in 44 patients with CSD who underwent surgical treatment and 20 control women who underwent total hysterectomy was assessed and the clinical symptoms in the presence and absence of CE were compared. In accordance with the presence of one or more CD138-positive plasma cells per high-power field, CE was classified as mild or severe group.

RESULTS

According to multivariate analysis, the presence of mild CE (OR 8.963, 95 % CI 2.177-36.907, p = 0.002) or severe CE (OR 21.773, 95 % CI 2.285-207.419, p = 0.007) was significantly associated with CSD. Mild CE (OR 12.390, 95 % CI 1.158-132.511, p = 0.037) or severe CE (OR 22.463, 95 % CI 1.657-304.541, P = 0.019) or depth of diverticulum (OR 1.294, 95 % CI 1.003-1.668, p = 0.047) was associated with prolonged menstruation in patients with CSD. The degree of CE in patients with CSD was positively correlated with the days of prolonged menstruation (r = 0.552, p < 0.001) and negatively correlated with haemoglobin level (r = -0.408, p = 0.038).

CONCLUSIONS

CE was associated with CSD and its clinical symptoms, including prolonged menstruation and decreased haemoglobin. The severity of clinical symptoms of CSD is associated with endometrial inflammation.

How does chronic endometritis influence pregnancy outcomes in endometriosis associated infertility? A retrospective cohort study

BACKGROUND

Endometriosis (EMS) and chronic endometritis (CE) frequently coexist. This study aimed to examine the impact of CE on reproductive outcomes in patients with EMS.

METHODS

We enrolled 685 patients with endometriosis-associated infertility from January 2018 to December 2020. The patients were divided into CE (318) and non-CE (367) groups. A subset of 123 clinically pregnant women from the CE group and 369 from the non-CE group was selected for detailed comparison. Pregnancy and delivery data were meticulously collected from hospital records and through telephone interviews.

RESULTS

CE was diagnosed in 46.42% of EMS patients. Higher pregnancy rates were observed in patients with Endometriosis Fertility Index (EFI) scores of 7-10. EMS patients with CE had increased risks of placenta previa (13.01%), gestational hypertension (5.69%), and cesarean sections (59.34%).

CONCLUSIONS

CE, which is prevalent among EMS patients, is linked to increased risks of pregnancy complications, including placenta previa, gestational hypertension, and cesarean delivery. Although combined hysteroscopy and laparoscopy improve pregnancy rates, they demand careful management of these complications.

Investigating bacteria-induced inflammatory responses using novel endometrial epithelial gland organoid models

Introduction

The endometrium plays a crucial role in early human pregnancy, particularly in embryo implantation, survival, and growth. However, invasion and infection by pathogens can lead to endometritis, infertility, and poor reproductive outcomes. Understanding the mechanisms of endometritis and its impact on fertility remains limited. An infection model using patient-derived endometrial epithelial gland organoids (EEGOs) was established to advance in vitro studies on endometritis and related infertility.

Methods

An EEGOs infection model was constructed and characterized from human endometrium, treating the organoids with estrogen and progesterone to observe changes in the proliferative and secretory phases. The organoids were infected with E. coli, and the release of inflammatory cytokines in the supernatant was detected using ELISA. RNA-seq was employed to analyze the differences before and after E. coli treatment, and differential gene mRNA expression was validated using real-time quantitative PCR. Additionally, the effect of E2 in alleviating inflammation was assessed through markers of receptivity (PAEP, LIF, ITGβ), proliferation (Ki67), and barrier repair (ZO-1).

Results

The constructed human EEGOs exhibited long-term expansion capability, genetic stability, and characteristic hormonal responses, strongly expressing epithelial markers (MUC1, E-Cadherin). After E. coli infection, the expression levels of inflammatory cytokines TNF-α, IL-8, and IFN-γ increased significantly (P < 0.05). RNA-seq indicated that the MAPK signaling pathway was activated post-infection, with increased expression levels of heat shock proteins and transcription factor mRNA. E2 treatment post-infection significantly decreased the mRNA expression of inflammatory genes IL-1β, IL8, IL6 and TNF-α compared to the E. coli infected group (P < 0.05). Additionally, the expression of genes related to receptivity, proliferation, and barrier repair was enhanced in the E2-treated organoids.

Conclusions

Our findings demonstrate that patient-derived EEGOs are responsive to bacterial infection and are effective models for studying host-pathogen interactions in bacterial infections. These organoids revealed the anti-inflammatory potential of E2 in alleviating E. coli-induced inflammation, providing insights into the mechanisms of endometritis and its impact on infertility. The study supports the use of EEGOs as valuable tools for understanding endometrial health and developing targeted treatments.

Impact of Diagnosis and Treatment of Chronic Endometritis on Outcomes Before Starting Assisted Reproductive Technology: A Retrospective Study

This study aimed to investigate the effect of diagnosis and treatment of chronic endometritis (CE) on the outcome of assisted reproductive technology (ART) with or without repeated implantation failure (RIF). This retrospective analysis included patients who underwent pathological examination for diagnosis of CE at Yamagata University Hospital. The examination was performed for all patients planned for ART with or without RIF. Patients who were examined within 6 months of the first oocyte retrieval or embryo transfer were included. We counted the number of CD138-positive cells within the endometrial stroma in patients' specimens and analyzed the patients' clinical information. Clinical rates of pregnancy and implantation were determined. A total of 80 women met the inclusion criteria: 13 CE-negative patients (17.3%) and 67 CE-positive patients (83.7%). A significant decrease was noted in the CD138-positive cell count between the first biopsy and second biopsy after CE treatment (p < 0.001). In addition, no significant differences were noted in ongoing pregnancy rates between the CE-negative patients and those who underwent CE treatment. The CD138-positive cell counts at first biopsy tended to be lower in each pregnancy group than in the non-pregnancy group. For patients planned to undergo ART, examination for diagnosis of CE with or without RIF could be considered. Pathological CD138-positive cell counts were considered useful for CE diagnosis and treatment decision-making. The study findings suggest the efficacy of antimicrobial agents in CE treatment, contributing to improved pregnancy outcomes.

Australasian recurrent pregnancy loss clinical management guideline 2024, part II

Part II of the Australasian guideline for the investigation and management of recurrent pregnancy loss (RPL) provides evidence-based guidance on the management of RPL provided. The implications of inherited and acquired thrombophilia with respect to RPL and suggestions for clinical management are provided. Autoimmune factors, including human leukocyte antigen, cytokines, antinuclear antibodies and coeliac antibodies, and guidance for management are discussed. Infective, inflammatory and endometrial causes of RPL are discussed in detail. Environmental and lifestyle factors, male factor and unexplained causes are outlined. Levels of evidence and grades of consensus are provided for all evidence-based statements.

Potential mechanisms and therapeutic strategies for LPS-associated female fertility decline

As a major component of the outer membrane of Gram-negative bacteria, lipopolysaccharide (LPS) can be recognized by toll-like receptors (TLRs) and induce inflammation through MyD88 or the TIR domain-containing adapter-inducing interferon-β (TRIF) pathway. Previous studies have found that LPS-associated inflammatory/immune challenges were associated with ovarian dysfunction and reduced female fertility. However, the etiology and pathogenesis of female fertility decline associated with LPS are currently complex and multifaceted. In this review, PubMed was used to search for references on LPS and fertility decline so as to elucidate the potential mechanisms of LPS-associated female fertility decline and summarize therapeutic strategies that may improve LPS-associated fertility decline.

Clinical utility of office hysteroscopy following failed in vitro fertilization-embryo transfer: A retrospective cohort study

OBJECTIVE

Despite its widespread use, in vitro fertilization (IVF) outcomes are challenged by implantation failure, largely due to factors such as embryo quality and endometrial receptivity. In this study, we investigated the clinical effect of office hysteroscopy (OH) on the subsequent frozen-thawed embryo transfer (FET) in infertile women who experienced a failed IVF-embryo transfer (IVF-ET) cycle.

METHODS

We included 577 infertile women who underwent OH because of a history of failed ET between October 2019 and September 2021. During OH, visible endometrial polyps (EPs) were diagnosed and removed by curette or biopsy forceps; chronic endometritis (CE) was diagnosed by histopathology and immunohistochemistry and treated with oral doxycycline (0.2 g/d) for 14 days. According to the hysteroscopic findings and endometrial pathology with immunohistochemistry, patients were divided into three groups: group A (n = 161) had CE with or without EPs, group B (n = 156) had EPs only, and group C (n = 260) had no CE or EPs.

RESULTS

In the following FET cycle, the implantation rates were 47%, 51%, and 45% (P = 0.411); the clinical pregnancy rates were 56%, 62%, and 55% (P = 0.436); the live birth rates were 45%, 51%, and 42% (P = 0.205); and the miscarriage rates were 18%, 16%, and 22% (P = 0.497) in groups A, B, and C, respectively. There were no significant differences among groups (P > 0.05).

CONCLUSION

OH is helpful for diagnosis and treatment of abnormal intrauterine environment in women with a failed IVF cycle and further improves their pregnancy outcome in the following FET.

Viral Infection in Endometritis: Is There an Important Role or Not?

Chronic endometritis (CE) is a frequent pathological condition that is defined as localized inflammation in the endometrium. Some adverse fertility consequences such as recurrent miscarriage and failure of implantation are associated with chronic endometritis. On the one hand, inflammation plays an important role in the pathogenesis of endometritis, and on the other hand, the role of viral infections in inducing inflammation can make this review strongly attractive and practical. We set out to provide an overview of viral infections as a potential etiology of CE pathophysiology through the alteration of an endometrial microenvironment and its association with infertility. To the best of our knowledge, this is the first review to demonstrate the role of viral infection in chronic endometritis, and whether or not infection ultimately plays a role..

The role and challenges of regulating endometrial microbiome in uterine health and diseases

The uterine environment provides necessary conditions for the existence of endometrial microbiota, which in turn plays an important role in maintaining the homeostasis of the uterine environment. The endometrial microbiome is highly susceptible to external factors such as age, hormones, menstrual, pregnancy, etc. When the microbiota is imbalanced, it will further promote the occurrence of uterine diseases such as endometritis and endometrial cancer. Regulating the microbiome of the endometrium is of positive significance for promoting uterine health. Among them, antibiotics, probiotics, prebiotics, and microbial transplantation may be important pathways for regulating endometrial microbiota in the future. However, there is currently no unified plan for evaluating the endometrial microbiota. In addition, due to the small sample size, it is easy to be contaminated by exogenous bacterial DNA, which poses great challenges for studying the mechanism of microbial community regulating uterine health. Therefore, there are still many areas worth exploring for the future of endometrial microbiome.

Overexpression of USP22 ameliorates LPS-induced endometrial stromal cells inflammation and modulates cells decidualization by inhibiting ferroptosis

Endometritis and the failure of decidualization of the endometrium are important factors contributing to the increased incidence of abortion. USP22 is associated with various inflammatory diseases and has been shown to be involved in endometrial decidualization in mice. This study aims to investigate whether USP22 is involved in the regulation of inflammatory response and decidualization in human endometrial stromal cells (hESCs). In this study, lipopolysaccharide (LPS) was used to induce inflammation in hESCs, and MPA combined with cAMP was used to induce decidualization of hESCs. USP22 overexpression vector was constructed to study the role of USP22 in endometritis. The results showed that the USP22 protein and mRNA levels were decreased in LPS-induced hESCs. LPS induction increased the levels of TNF-α, IL-1β, and IL-6, as well as the expression of iNOS and COX2 proteins in hESCs. In the LPS group, the levels of F-actin, PRL, IGFBP1, SLC7A11, and GPX4 proteins decreased, while the levels of lipid peroxidation and total iron content increased. Additionally, the levels of ACSL4 and TFR1 proteins were up-regulated. Overexpression of USP22 reversed LPS-induced cellular inflammation, attenuated decidualization, and inhibited ferroptosis. However, the use of ferroptosis inducers diminished the regulatory effects of USP22 on inflammatory responses and decidualization. In summary, these suggested that USP22 reduces the LPS-induced inflammatory response and regulates the decidualization of hESCs, and possibly involving ferroptosis.

Correlation of hysteroscopic findings of chronic endometritis with CD138 immunohistochemistry and their correlation with pregnancy outcomes

PURPOSE

To investigate the correlation between hysteroscopic findings of chronic endometritis and CD138 immunohistochemistry positive in endometritis and to analyze the pregnancy outcomes and associated risk factors following embryo transfer in women diagnosed with chronic endometritis via hysteroscopy.

METHODS

A retrospective observational study carried out at the Reproductive Medicine Center of Tangdu Hospital of Air Force Medical University, from January 2021 to December 2021, was performed by obtaining data from 194 medical records of women who underwent hysteroscopies for infertility and were diagnosed with chronic endometritis based on Delphi criteria. Spearman correlation analysis was used to evaluate the correlation between hysteroscopic findings and endometrial CD138 immunohistochemistry. The study also observed the differences in relevant indexes between the CD138-positive and CD138-negative groups after embryo transfer and analyzed factors influencing implantation failure using logistic regression analysis.

RESULTS

The correlation analysis between hysteroscopic findings and CD138 immunohistochemistry showed that micropolyps were correlated with CD138 immunohistochemistry positivity. The correlation coefficient was 0.32 (P < 0.01). After embryo transfer, the clinical pregnancy rate of the CD138-positive group was lower compared to that of the CD138-negative group [64.79% (46/71) vs. 81.30% (100/123), P < 0.05]. The results of the multivariate logistic regression analysis revealed that age (P = 0.43) and CD138 immunohistochemistry positivity (P = 0.008) were the independent risk factors for predicting whether or not embryo implantation was successful.

CONCLUSION

Hysteroscopic findings do not correlate strongly with endometrial CD138 immunohistochemistry, and chronic endometritis cannot be diagnosed by hysteroscopy alone. CD138 immunohistochemistry positivity is an independent factor contributing to the decrease in clinical pregnancy rate following embryo transfer.

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.

Development of a rapid test to determine endometritis of cows after calving

Background and Aim

Postpartum uterine disease, such as endometritis, is widespread in highly productive dairy cows, leading to fertility problems and economic losses. Despite existing diagnostic methods, early and effective detection of uterine infections remains problematic due to the subclinical nature of some conditions. This study aimed to develop and evaluate a rapid diagnostic test for endometritis in cows on different days postpartum (PP).

Materials and Methods

The study was carried out on dairy Holstein-Friesian cows (n = 121) kept on farms in northern Kazakhstan. The study included both clinically normal cows and those diagnosed with endometritis, ensuring a comprehensive evaluation of the diagnostic methods across different stages of uterine health. The following laboratory tests were performed to diagnose and evaluate the presence and severity of endometritis in the cows: Nagorny-Kalinovsky test, Whiteside test, Katerinov test, Gavrish silver nitrate test, peroxide test, and clinical tests (rectal and vaginal examination). These tests were specifically chosen to identify inflammatory processes in the uterus, particularly focusing on detecting endometritis.

Results

From day 21 to 30 PP, rectal and vaginal examinations were 32% and 28% more effective than the Nagorny-Kalinovsky test and the Whiteside test. From day 61 postpartum, the Whiteside test was 37.5% more effective than the Nagorny-Kalinovsky test. Comparatively, among laboratory diagnostic methods from days 10 to 110 PP, the peroxide test showed the greatest effectiveness in identifying 80.9% of sick animals. In sick animals from day 10 to 20 PP, during the interaction of the cervicovaginal mucus with 10%, 20%, and 30% hydrogen peroxide (H2O2), an 8.1 ± 1.9-8.8 ± 1.6 cm foam column was formed within 4-5 min.

Conclusion

The experiment showed that a 10% H2O2 solution yielded better results. Using H2O2 as a diagnostic agent for endometritis in cows has several advantages, including ease of use, it does not require special laboratory conditions and provides a visual reading of the reaction within 4-5 min. A limitation of this study is the focus on H2O2 without exploring other potential reagents that may enhance diagnostic accuracy. Future research could explore the long-term stability of cervicovaginal mucus samples and investigate the integration of additional substances that may expedite the detection of subclinical endometritis and improve the clarity of diagnostic results.

The Therapeutic Potential of Lactobacillus crispatus for Chronic Endometritis: A Comprehensive Clinical Trial and Experimental Investigation

Chronic endometritis (CE) is common in patients with infertility, and it is challenging to treat with antibiotics as bacteria often acquire resistance to the antibiotics, which leads to frequent recurrence of the condition. Probiotics, especially Lactobacillus species, are known for their usefulness in treating reproductive infections. This study evaluated Lactobacillus crispatus chen 01 (L. crispatus chen 01) isolated from healthy women who were 22-30 years old and married with children. In vitro experiments showed that L. crispatus chen 01 inhibited pathogens and reduced inflammation in CE mice by downregulating inflammatory proteins (TLR, MyD88, and p65/p-p65; L + Abx vs M, P < 0.01), improving histopathological features, and inhibiting bacterial growth. It also regulated endometrial processes, such as enhancing embryo implantation (BMP2 and Wnt4, L + Abx vs M, P < 0.01) via the Wnt/β-catenin pathway, leading to increased pregnancy rates (L + Abx vs M, 100% vs 0%) in mice. In clinical trials, L. crispatus chen 01 improved progesterone levels (P = 0.0038), pregnancy rates (C vs Abx + L. c, 76.19% vs 87.18%), and pathological changes in CE patients. The findings from this study identify the administration of L. crispatus chen 01 as a promising intervention for CE that could improve pregnancy rates.

Clinicopathological Aspects of Dilation and Curettage (D&C) Biopsies Taken from Patients Living at High Altitude in Taif, KSA, with a Special Emphasis on Chronic Endometritis

BACKGROUND

Chronic endometritis (CE) is a persistent inflammation of the uterine lining. Although it has a minimal clinical presentation, CE adversely affects the reproductive ability of women. The aims of this study were to detect pathological endometrial patterns in D&C biopsies and to evaluate chronic endometritis in patients living in a high-altitude area (1800 m above sea level) in order to determine the clinical pathological features and prevalence.

MATERIALS AND METHODS

A cross-sectional study conducted at King Faisal Maternity Hospital included 100 samples of D&C biopsies from women complaining of various gynecological symptoms not due to gestational causes. The biopsies underwent tissue processing, H&E staining, and CD138 detection. Blood samples were taken for serological detection of infectious diseases, complete blood count, and chemical parameters.

RESULTS

The mean age of women in the study with CE was 48.5 ± 8.5 years, and that of those without CE was 46.9 ± 9.7 years. The most common complaints were abnormal uterine bleeding, accounting for 83%. CE was present in 8% of cases, and there was a nonsignificant difference in hematological parameters between women with CE and those with other pathological diagnoses. There were also nonsignificant differences in chemical parameters, except for FSH and LH levels, which showed a significant difference, with p-values of 0.05 and 0.02, respectively. It can be concluded that the most common gynecological complaint of women in this study was abnormal uterine bleeding.

CONCLUSIONS

The most commonly diagnosed pathological endometrial disorder in D&C biopsies was disordered proliferative endometrium, followed by endometrial polyps and endometrial hyperplasia. All of these are usually associated with hormonal disturbance, which appeared to be very common in the women in this study. The prevalence of chronic endometritis detected in our study was 8%, which is relatively high.

Chronic endometritis and recurrent reproductive failure: a systematic review and meta-analysis

Background

The endometrium holds a crucial role in reproduction by supporting blastocyst adhesion, cytotrophoblast invasion and fetal development. Among the various uterine disorders, endometritis, particularly chronic endometritis (CE), has gained attention due to its association with adverse reproductive outcomes (recurrent pregnancy loss (RPL), recurrent implantation failure (RIF), and infertility). The association between CE and adverse reproductive outcomes stresses the necessity for comprehensive diagnostic and therapeutic strategies to optimize fertility outcomes and support individuals in their journey towards parenthood.

Aim

To explore the relationship between CE and reproductive disorders.

Methods

Following PRISMA guidelines, a systematic review and meta-analysis using published data from 1990 to 2024 were carried out.

Results

A population of 1,038 women was included. Regarding CE-infertility association, a positive correlation was found, with 19.46% CE rate in infertile women compared to 7.7% in controls (OR: 2.96, 95% CI 1.53-5.72, p 0.001). No significant association was observed between RIF and CE (OR: 1.10, 95% CI 0.26-4.61, p 0.90), CE rates in both groups were relatively comparable, with 6.35% in women with RIF and 5.8% in controls. On the opposite, a strong association between CE and RPL was found, reporting a CE rate of 37.6% in RPL cases compared to 16.4% in controls (OR: 3.59, 95% CI 2.46-5.24, p < 0.00001).

Conclusions

CE appears to be associated to infertility and RPL, while no significant association was noted in cases of RIF.

Systematic review registration

https://www.crd.york.ac.uk/prospero/#recordDetails PROSPERO, identifier CRD42024541879.

Revolutionizing chronic endometritis diagnosis: real-time polymerase chain reaction unveils microbial pathogens in Indian women with abnormal bleeding and reproductive challenges

Background

This study aimed to assess the utility of real-time-polymerase chain reaction (PCR) for diagnosing chronic endometritis (CE) by targeting 11 prevalent pathogens and to compare the outcomes with conventional culture-based diagnosis.

Study Design

A retrospective analysis was conducted on 500 patients with clinical conditions such as abnormal bleeding, in vitro fertilization failure, recurrent implantation failure, recurrent miscarriage, and recurrent pregnancy loss. The prevalence of 11 key pathogens associated with CE was evaluated in endometrial biopsy samples.

Results

In our study, PCR identified 318 cases (63.6%) positive for at least one of the 11 investigated pathogens, while culture-based methods detected 115 cases (23%). Predominant pathogens detected by PCR included Enterococcus faecalis (E. faecalis) (19%), Escherichia coli (E. coli) (6.8%), Staphylococcus aureus (S. aureus) (9%), Mycoplasma hominis (5%), Mycoplasma genitalium (6.2%), Streptococcus agalactiae (S. agalactiae) (4.2%), Ureaplasma urealyticum (4%), nontuberculous Mycobacterium (5.2%), Mycobacterium tuberculosis (1.2%), Neisseria gonorrhoeae (0.6%), and Chlamydia trachomatis (2.4%). Standard culture methods identified E. faecalis (10.8%), S. aureus (6.2%), E. coli (3.8%), and S. agalactiae (2.2%).

Conclusion

The DICE panel proves itself as a swift, precise, and cost-effective diagnostic tool for detecting both culturable and nonculturable endometrial pathogens in CE. Demonstrating superiority, the Molecular method outshines microbial culture, ensuring accurate and sensitive detection of CE-associated pathogens, harmonizing seamlessly with histology and hysteroscopy findings.

Oil-soluble contrast medium bathing attenuated endometrial inflammation and improved endometrial receptivity in women with recurrent implantation failure: a descriptive study

BACKGROUND

The oil-soluble contrast medium used in hysterosalpingography has been shown to have a fertility-enhancing effect, but the underlying mechanism is unclear, especially regarding the role of window of implantation (WOI). This study aimed to assess the endometrial immunological impact of the WOI before and after bathing with the oil-soluble contrast medium in women with recurrent implantation failure (RIF).

METHODS

This descriptive study involved two medical centers between December 18, 2019, and December 30, 2020. We included infertile women who underwent three or more transfer cycles, cumulative transplantation of at least four high-quality cleavage-stage embryos or three high-quality blastocysts without clinical pregnancy, and high-quality frozen embryos that were still available for implantation. Patients received 5 ml of ethiodized poppyseed oil bathing, endometrial biopsy around bathing, and frozen-thawed embryo transfer (FET) within four menstrual cycles after bathing. Patients were excluded if failure to complete anyone. Data on the baseline characteristics and clinical data of the FET cycles were collected, and endometrial biopsy specimens were collected in the luteal phase before and after bathing and subjected to immunohistochemistry. The number of CD56 and CD138 positive cells and H-score of expression of ανβ-3 and HOXA10 in endometrium were collected.

RESULTS

Thirty-four patients were initially enrolled in the study; ultimately, twelve patients with a median age of 32.5 years (range 27-40 years) completed the research. The median number of embryo transfer cycles was three (range 3-8). A total of 4 of 12 women (33.33%) were diagnosed with chronic endometritis before oil-soluble contrast bathing. After bathing, the median numbers of CD138-positive cells in endometrium decreased from 0.75 (range 0-13.5) to 0.65 (range 0-6), P = 0.035; additionally, the H-score of expression of ανβ-3 in endometrium increased from 148.50 ± 31.63 to 175.58 ± 31.83, P < 0.001. The thickness of the endometrium also significantly increased (8.90 ± 1.45 mm vs.10.11 ± 1.98 mm, P = 0.005). However, no consistent changes were found in the expression of CD56 and HOXA10 in the endometrium. Five patients experienced biochemical pregnancies (41.67%), four had clinical pregnancies (33.33%), and three achieved live births following oil-soluble contrast bathing (25%).

CONCLUSIONS

These results suggest that oil-soluble contrast medium bathing decreased CD138-positive cells and upregulated expression of ανβ-3 during WOI in patients with RIF. This histological impact of endometrium may result in enhanced fertility during FET cycles. Investigating the ability of intrauterine bathing with lower-dosage oil-soluble contrast to improve pregnancy in the RIF population is warranted.

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.

Correlation between hysteroscopic features and specific microbial species in women with chronic endometritis

Objective and rationale

Chronic endometritis (CE) has recently been associated with unexplained infertility and recurrent miscarriages. The current gold standard for CE detection is histopathological examination. However, office hysteroscopy and endometrial cultures are also significant, due to the possible link between CE and various microorganisms. Bacterial colonization of the endometrium has been associated with reduced success rates of in vitro fertilisation embryo transfer. Few studies have tried to correlate CE hysteroscopy findings with pathogenic microorganisms. This prospective cohort study sought to establish whether hysteroscopic diagnostic lesions correlate with specific microbial species.

Methods

The study encompassed women undergoing diagnostic tests for a range of subfertility health issues. 189 women completed the standard office diagnostic hysteroscopy (DH). 181 had also endometrial samples taken for microbial culture investigation. Correlation analysis (χ2 and Fisher's exact test) between hysteroscopic findings suggestive of CE and endometrial cultures was carried out. Logistic regression models were also fitted to measure whether a positive endometrial culture could affect CE conditions.

Results

A significant association of E. coli was observed between the hysteroscopically characterized CE + group with focal hyperplasia, when compared to the non-CE group. Logistic regression analysis revealed that women positive for E. coli were 4.423 times more likely to have focal endometrial hyperplasia. No other significant correlations were identified between DH and positive endometrial cultures.

Conclusions

The presence of E. coli in the endometrium was significantly correlated with focal hyperplasia findings from hysteroscopy, emphasizing the importance of microbial cultures in the diagnosis and targeted treatment of CE in women with subfertility.

Exploring the therapeutic effect of Pen Yan Kang Fu Decoction on SPID rats based on LIF/JAK2/STAT3 signaling pathway

Tubal inflammation, endometritis, and uterine adhesions due to post-pelvic inflammatory disease (SPID) are important causes of infertility. Chronic endometritis (CE) belongs to SPID, which seriously affects women's reproductive health, quality of life, and family harmony, and is a hot and difficult problem in clinical research. The efficacy of Pen Yan Kang Fu Decoction (PYKFD) has been verified in long-term clinical practice for chronic endometritis infertility caused by the SPID. Numerous studies have confirmed that the LIF/JAK2/STAT3 signaling pathway is important in embryo implantation and development, and endometritis infertility is close to LIF/JAK2/STAT3. In vivo results showed that PYKFD increased endometrial receptivity, repaired uterine tissue damage, and regulates the expression of endometrial receptivity-related factors ER (estrogen receptor), PR (progesterone receptor), CD31, and integrin αvβ3, and induced the transduction of LIF/JAK2/STAT3 signaling pathway. PYKFD can also regulate the expression of IL-6. The results of in vitro experiments showed that PYKFD regulates the behavior of rat endometrial epithelial cells (REECs) involving LIF. In conclusion, PYKFD can improve endometrial receptivity and promote endometrial repair by LIF/JAK2/STAT3 signaling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-024-03981-0.

The Role of Prevotella Species in Female Genital Tract Infections

Female genital tract infections (FGTIs) include vaginal infections (e.g., bacterial vaginosis [BV]), endometritis, pelvic inflammatory disease [PID], and chorioamnionitis [amniotic fluid infection]. They commonly occur in women of reproductive age and are strongly associated with multiple adverse health outcomes including increased risk of HIV/sexually transmitted infection acquisition and transmission, infertility, and adverse birth outcomes such as preterm birth. These FGTIs are characterized by a disruption of the cervicovaginal microbiota which largely affects host immunity through the loss of protective, lactic acid-producing Lactobacillus spp. and the overgrowth of facultative and strict anaerobic bacteria. Prevotella species (spp.), anaerobic Gram-negative rods, are implicated in the pathogenesis of multiple bacterial FGTIs. Specifically, P. bivia, P. amnii, and P. timonensis have unique virulence factors in this setting, including resistance to antibiotics commonly used in treatment. Additionally, evidence suggests that the presence of Prevotella spp. in untreated BV cases can lead to infections of the upper female genital tract by ascension into the uterus. This narrative review aims to explore the most common Prevotella spp. in FGTIs, highlight their important role in the pathogenesis of FGTIs, and propose future research in this area.

Proximal tubal occlusion first or oocyte retrieval first for patients with hydrosalpinx?

PURPOSE

Our study aimed to investigate the best time to manage hydrosalpinx to improve pregnancy outcomes during in vitro fertilization-embryo transfer (IVF-ET).

METHODS

Patients with hydrosalpinx who received IVF treatment were analyzed retrospectively. And two groups were included to compare the effects of different timing treatment of hydrosalpinx on IVF pregnancy outcomes, "Proximal Tubal Occlusion First Group" (Group Ligation-COH) and "Oocyte Retrieval First Group" (Group COH-Ligation). The main outcome measures included: ovarian response indexes, laboratory indexes and clinical pregnancy outcomes. Univariate and multivariate Logistic regression analysis was performed for outcome indicators, and the odds ratios (OR) and 95% confidence interval (CI) were used.

RESULTS

A total of 1490 patients were included (n = 976 Ligation-COH and n = 514 COH-Ligation). The Gn starting dose and MII rate in group Ligation-COH were significantly higher than those in group COH-Ligation (203.33 ± 58.20 vs. 203.33 ± 58.20, 81.58% vs. 80.28%, P < 0.05). The number of oocytes obtained and the number of available D3 embryos in group COH-Ligation were higher than those in group Ligation-COH (15.10 ± 7.58 vs. 13.45 ± 6.42, 10.92 ± 5.81 vs. 9.94 ± 5.15, P < 0.05). Although the number of ET cycles per IVF cycle in group COH-Ligation was higher than that in group Ligation-COH (1.88 ± 1.00 vs. 1.48 ± 0.70, P < 0.05), the biochemical pregnancy rate, clinical pregnancy rate, multiple pregnancy rate, live birth rate and cumulative live birth rate in group Ligation-COH were significantly higher than those in group COH-Ligation (60.83% vs. 46.27% for biochemical pregnancy, 55.69% vs. 38.5% for clinical pregnancy, 26.18% vs. 17.74% for multiple pregnancy, 47.08% vs. 25.26% for live birth, 69.47% vs. 47.47% for cumulative live birth, P < 0.05), and the miscarriage rate in group Ligation-COH was lower than that in group COH-Ligation (10.47% vs. 17.20 for early abortion, 4.49% vs. 15.86% for late abortion, P < 0.05). In logistic regression analysis, after adjustment for age and multiple factors, the above results were still statistically significant differences (P < 0.001). For elderly patients, the clinical pregnancy rate, multiple birth rate and live birth rate in group Ligation-COH were also higher than those in group COH-Ligation (P < 0.001). No significant differences were detected for patients with diminished ovarian reserve.

CONCLUSIONS

For the choice of ligation operation time, we recommend that patients choose tubal ligation first and then ovulation induction and oocyte retrieval treatment.

The efficacy of vaginal treatment for non-Lactobacillus dominant endometrial microbiota-A case-control study

AIM

Reduced Lactobacillus occupancy in the uterine microflora has been associated with implantation failure. This study aimed to evaluate a treatment for improving the uterine microflora.

METHODS

This study included patients diagnosed with repeated implantation failure-defined as failure to achieve pregnancy after two or more transfers of viable embryos-who were classified as non-Lactobacillus dominant. Treatment A comprised oral administration of antibiotics for 1 week, followed by oral probiotic butyrate tablets (3 g/day) for approximately 30 days. Treatment B comprised a 1-week course of oral (750 mg/day) and vaginal (250 mg/day) metronidazole, followed by a 1-week intravaginal administration of probiotic capsules (1 capsule/day) and continued oral administration of probiotics (1 capsule/day). Both treatments were compared in terms of efficacy in improving vaginal flora. Improvement was defined as Lactobacillus occupancy >90% or an increase in Lactobacillus occupancy >20%.

RESULTS

Seven (41.2%) of 17 patients in the Treatment A group improved in response to the treatment. Contrastingly, 9 (90.0%) of 10 patients improved in the Treatment B group (p = 0.0127). Following treatment, Lactobacillus occupancy in the Treatment B group (62.9% ± 12.7%) was significantly higher than that in the Treatment A group (5.7% ± 9.8%) (p = 0.0242).

CONCLUSIONS

This study demonstrates the effectiveness of combining antibiotics and probiotics in vaginal formulations for treating abnormal uterine microflora. However, its potential impact on in vitro fertilization outcomes remains unclear and warrants further investigation through larger, more comprehensive studies.

Deciphering the role of female reproductive tract microbiome in reproductive health: a review

Relevant studies increasingly indicate that female reproductive health is confronted with substantial challenges. Emerging research has revealed that the microbiome interacts with the anatomy, histology, and immunity of the female reproductive tract, which are the cornerstone of maintaining female reproductive health and preventing adverse pregnancy outcomes. Currently, the precise mechanisms underlying their interaction and impact on physiological functions of the reproductive tract remain elusive, constituting a prominent area of investigation within the field of female reproductive tract microecology. From this new perspective, we explore the mechanisms of interactions between the microbiome and the anatomy, histology, and immunity of the female reproductive tract, factors that affect the composition of the microbiome in the female reproductive tract, as well as personalized medicine approaches in managing female reproductive tract health based on the microbiome. This study highlights the pivotal role of the female reproductive tract microbiome in maintaining reproductive health and influencing the occurrence of reproductive tract diseases. These findings support the exploration of innovative approaches for the prevention, monitoring and treatment of female reproductive tract diseases based on the microbiome.

Platelet rich plasma alleviates endometritis induced by lipopolysaccharide in mice via inhibiting TLR4/NF-κB signaling pathway

BACKGROUND

Endometritis is an inflammatory reaction of the lining of uterus, leading to the occurrence of infertility. Platelet rich plasma (PRP) has been proven to exhibit extremely effective for the treatment of endometrium-associated infertility, but the mechanism of its prevention for endometritis remains unclear.

OBJECTIVE

The present study aimed to investigate the protective effect of PRP against endometritis induced by lipopolysaccharide (LPS) and elucidate the mechanism underlying these effects.

METHODS

Mouse model of endometritis was established by intrauterine perfusion of LPS. PRP intrauterine infusion was administered at 24 h after LPS induction. After another 24 h, the uterine tissues were harvested to observe histopathological changes, production of proinflammatory cytokines, variation of the Toll-like receptor 4/nuclear factor κB (TLR4/NF-κB) signaling pathways, and validated the anti-inflammatory effect of PRP. The myeloperoxidase (MPO) activity and concentration of nitric oxide (NO) were determined using assay kit. Proinflammatory chemokines (tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6)) were measured by ELISA and Real-Time PCR. The activity of TLR4/NF-κB pathway in uterine tissues was measured by Western blotting.

RESULTS

Hematoxylin-eosin staining (H&E) appeared that PRP remarkably relieved the impairment of uterine tissues. Detection of MPO activity and concentration of NO revealed that PRP treatment distinctly mitigated infiltration of inflammatory cells in mice with endometritis induced by LPS. PRP treatment significantly affected the expression of TNF-α, IL-1β, and IL-6. PRP was also found to suppress LPS-induced activation of TLR4/NF-κB pathway.

CONCLUSION

PRP effectively alleviates LPS-induced endometritis via restraining the signal pathway of TLR4/NF-κB. These findings provide a solid foundation for PRP as a potential therapeutic agent for endometritis.

Unveiling the protective effects of BMSCs/anti-miR-124-3p exosomes on LPS-induced endometrial injury

Researchers have reported that miR-124-3p is highly expressed in patients with chronic endometritis. However, the underlying mechanism of miR-124-3p in the development of endometritis remains unclear. This study constructed an in vitro endometrial cell injury model by treating HEECs with 2 μg/mL LPS for 48 h. Then, 1 mg/kg LPS was injected into both sides of the mouse uterus to construct an in vivo endometrial injury model. The expression of miR-124-3p in human endometrial epithelial cells (HEECs) was assessed using RT‒qPCR. Exosomes were separated from bone marrow-derived mesenchymal stem cells (BMSCs) and cocultured with HEECs. A dual-luciferase reporter assay was performed to confirm the relationship between miR-124-3p and DUSP6. The results indicated that LPS inhibited HEEC viability in a time- and dose-dependent manner. The miR-124-3p inhibitor reversed the LPS-induced apoptosis and inhibition of HEEC viability. In addition, miR-124-3p could be transferred from BMSCs to HEECs by exosomes. Exosomes were derived from BMSCs treated with an NC inhibitor (BMSCs/NC Exo) or miR-124-3p inhibitor (BMSCs/anti-miR-124-3p Exo). In addition, BMSCs/anti-miR-124-3p Exo abolished the LPS-induced inhibition of HEEC viability and proliferation by inducing HEEC apoptosis. Moreover, BMSCs/anti-miR-124-3p Exo alleviated the LPS-induced inflammation of HEECs by upregulating DUSP6 and downregulating p-p65 and p-ERK. Furthermore, in an LPS-induced in vivo endometrial injury model, BMSCs/anti-miR-124-3p Exo increased the expression level of DUSP6 and decreased the expression levels of p-p65 and p-ERK. BMSCs/anti-miR-124-3p Exo protected against LPS-induced endometrial damage in vitro and in vivo by upregulating DUSP6 and downregulating p-p65 and p-ERK1/2. This study showed that BMSCs/anti-miR-124-3p Exo might be a potential alternative for the treatment of endometritis.

The effect of previous induced abortion history on the assisted reproduction outcomes

PURPOSE

To study whether the history of induced abortion has an effect on the assisted reproduction outcomes in patients undergoing in vitro fertilization-embryo transfer (IVF-ET).

METHODS

3045 patients who underwent IVF-ET in the Department of Human Reproductive Center of Renmin Hospital from January 2017 to June 2021. They were divided into two groups according to whether there was a history of induced abortion in the past, and the outcomes were compared between the two groups.

RESULTS

The clinical pregnancy rate in the group with induced abortion history was lower than that in the group without induced abortion history (63.1% vs 67.1%), but the difference was not statistically significant (P = 0.059). The spontaneous abortion rate in the group with induced abortion history was higher than that in the group without induced abortion history (14.9% vs 11.2%) (P = 0.044). The live birth rate in the group with induced abortion history was lower than that in the group without induced abortion history (52.8% vs 59.0%) (P = 0.006). Stepwise logistic regression analysis showed that endometrial thickness (OR = 0.928, 95% CI = 0.886 ~ 0.972, P = 0.002) and live birth rate (OR = 0.682, 95% CI = 0.495 ~ 0.939, P = 0.019) were negatively correlated with induced abortion history. The rate of spontaneous abortion (OR = 1.452, 95% CI = 1.042 ~ 2.024, P = 0.028) was positively correlated with the history of induced abortion.

CONCLUSIONS

The previous history of induced abortion is related to the outcomes of IVF /ICSI-ET, the endometrial thickness on HCG trigger day decreased, the risk of spontaneous abortion increased and the live birth rate decreased in patients with induced abortion history when undergoing IVF/ICSI-ET.

Impact of a positive Chlamydia trachomatis serology on cumulative IVF live birth rate

RESEARCH QUESTION

Does positive Chlamydia trachomatis serology have an impact on the cumulative live birth rate from IVF?

DESIGN

A retrospective matched cohort study compared women with positive Chlamydia trachomatis serology (group A) who underwent IVF treatment between January 2016 and December 2021 with a control group of women with negative Chlamydia trachomatis serology (group B). The main outcome measures were the cumulative live birth rate per IVF cycle and the live birth rate per embryo transfer. Secondary outcomes were the cumulative rates of clinical pregnancy, ectopic pregnancy and pregnancy loss calculated per IVF cycle and per embryo transfer.

RESULTS

A total of 151 women in group A were matched 1:2 to 302 women in group B, representing 220 and 440 IVF cycles, respectively. Women with a history of Chlamydia trachomatis infection had a significantly higher rate of tubal obstruction (P < 0.001), excluded or operated hydrosalpinx (P = 0.002) and/or history of chronic endometritis (P < 0.001). There were no statistically significant differences between the two groups in the mean number of mature oocytes retrieved, fertilization rate or implantation rate. The IVF cumulative live birth rate per cycle was similar in the two groups (36.7% in group A versus 34.9% in group B, P = 0.692). The cumulative rates of clinical pregnancy, pregnancy loss, biochemical pregnancy and ectopic pregnancy were comparable between the two groups.

CONCLUSION

Positive Chlamydia trachomatis serology has no impact on IVF pregnancy outcomes.

Relationship between chronic endometritis and fallopian tube obstruction and its influence on pregnancy outcome after fallopian tubal recanalization

Background

Chronic endometritis (CE), frequently asymptomatic, is associated with female infertility. Fallopian tube obstruction (FTO) is also one of the factors contributing to female infertility. More than 90% of cases of proximal FTO can be successfully treated after fallopian tubal recanalization (FTR) and the spontaneous pregnancy rate of treated women after FTR is only about 30%. Potential factors affecting the success rate of FTR remain unclear. We speculate that CE may be one of the reasons affecting the recanalization of the fallopian tubes.

Objectives

To identify the correlation between CE and FTO, as well as the influence of CE on pregnancy outcomes following FTR.

Design

Retrospective observational study.

Methods

We retrospectively analyzed 498 women of childbearing age who underwent laparoscopy and hysteroscopy surgery for infertility. Endometrial samples were collected during surgery for CD138 immunohistochemistry staining for the diagnosis of CE. Based on the results of the tubal patency test, they were divided into two groups: the fallopian tubal patency group and the proximal FTO group. The prevalence of CE was compared between these two groups. All women with FTO underwent FTR during the operation until successful treatment was achieved. Pregnancy outcomes were assessed after a 12-month follow-up period following the procedures. Logistic regression was used to analyze factors that might affect pregnancy after FTR.

Results

The prevalence of CE in women with tubal obstruction was 30.5%, which was significantly higher than that in the fallopian tubal patency group (10.75%), p < 0.001. After FTR, the prevalence of CE in non-pregnant women was 40.18%, which was higher than that in pregnant women (40.18% vs 13.11%), and the difference was significant (p < 0.001). Multiple regression analysis showed that CE was a significant risk factor for FTO (OR: 2.54, 95% CI: 1.368-4.717, p < 0.05). In addition, CE was identified as a risk factor for infertility after FTR (OR: 4.730, 95% CI: 2.012-11.122).

Conclusion

The presence of CE seems to decrease the likelihood of achieving spontaneous pregnancy following FTR. This observation underscores the clinical importance of early detection and treatment of CE, emphasizing the necessity for immediate intervention to prevent potential fertility complications.

The Clinical Application of Platelet-Rich Plasma in the Female Reproductive System: A Narrative Review

Platelet-rich plasma is an autologous plasma containing platelets prepared from fresh whole blood drawn from a peripheral vein. Through processing, it can be prepared to contain supraphysiologic levels of platelets at three to five times greater than the level of normal plasma. PRP has been explored both in vivo and ex vivo in the human endometrium model in its ability to harness the intrinsic regenerative capacity of the endometrium. Intrauterine autologous PRP infusions have been shown to increase endometrial thickness and reduce the rate of intrauterine adhesions. In the setting of recurrent implantation failure, intrauterine infusion of PRP has been shown to increase clinical pregnancy rate. PRP also appears to hold a potential role in select patients with premature ovarian insufficiency, poor ovarian responders and in improving outcomes following frozen-thawed transplantation of autologous ovarian tissue. Further studies are required to explore the potential role of PRP in reproductive medicine further, to help standardise PRP protocols and evaluate which routes of administration are most effective.

Hysteroscopic features suggestive of chronic endometritis: a systematic review

The purpose of this systematic review is to identify common hysteroscopic findings suggestive of endometritis, chronic or subclinical, based on current scientific evidence. Data sources were MEDLINE, Embase, PubMed and other sources of grey literature. Four (4) authors independently selected studies addressing hysteroscopic detection of CE based on specific and clearly stated hysteroscopic criteria. The diagnosis was confirmed by histologic assessment, as stated in the materials and methods of these studies included. The initial search identified 599 studies, of which 21 met the inclusion criteria. Significant heterogeneity among published studies on Chronic endometritis (CE) remains the main limitation in performing a metanalysis and further analysis of diagnostic accuracy on the subject. Hysteroscopy is an important diagnostic tool in cases of chronic endometritis when accompanied by endometrial biopsies. Clinicians relate hyperaemia and endometrial oedema with chronic endometritis while more than half include micropolyposis as a pathognomonic feature of this subclinical condition. Micropolyps, stromal oedema, haemorrhagic spots, strawberry aspect, and hyperaemia are proposed as adequate indicators of hysteroscopic evidence of CE according to the literature. The impact of CE in long-term reproductive outcomes remain unclear, thus clinicians ought to communicate this to the patients and provide treatment where clinically appropriate. In addition, we present hysteroscopic images of histologically confirmed CE cases that could play the role of a hysteroscopic atlas.

Chronic endometritis incidence in infertile women with and without polycystic ovary syndrome: a propensity score matched study

BACKGROUND

Polycystic ovary syndrome (PCOS) is known to be associated with chronic low-grade inflammation and endometrial dysfunction. Chronic endometritis (CE) is a type of local inflammation that can contribute to endometrial dysfunction in infertile women. Some clinicians recommend screening for CE in women at high risk, such as those with endometrial polyps. However, it is still uncertain whether there is a relationship between PCOS and CE, as well as whether women with PCOS require enhanced screening for CE. This study was to assess the incidence of CE among infertile women with PCOS by hysteroscopy combined with histopathology CD138 immunohistochemical staining of endometrium.

METHODS

A total of 205 patients in the PCOS group and 4021 patients in the non-PCOS group from July 2017 to August 2022 were included in this retrospective study. After nearest-neighbor 1:4 propensity score matching (PSM), 189 PCOS patients were matched with 697 non-PCOS patients. Basic information was recorded. The CE incidence was compared. The risk factors affecting CE incidence were also analyzed.

RESULTS

No significantly higher CE incidence in infertile women with PCOS were found either in total analysis or after PSM (P = 0.969; P = 0.697; respectively). Similar results were discovered in the subgroup of Body Mass Index (BMI) (P = 0.301; P = 0.671; P = 0.427; respectively) as well as the four PCOS phenotypes (P = 0.157). Intriguingly, the incidence of CE increased as BMI increased in the PCOS group, even though no significant differences were found (P = 0.263). Multivariate logistic regression showed that age, infertility duration, infertility type, PCOS, and obesity were not the independent risk factors affecting CE incidence.

CONCLUSION

The incidence of CE in PCOS patients did not significantly increase compared to non-PCOS patients. Similarly, no significant differences in the incidence of CE were observed among different PCOS phenotypes. The current evidence does not substantiate the need for widespread CE screening among PCOS women, potentially mitigating the undue financial and emotional strain associated with such screenings.

Cellulomonas endometrii sp. nov.: a novel bacterium isolated from the endometrial microbiota

An isolate of a bacterium recovered from an endometrial biopsy failed to be identified by MALDI-TOF mass spectrometry and was subjected to 16S rRNA sequencing. The obtained sequence was compared by BLASTn against the NCBI database, which revealed that the most closely related species was Cellulomonas hominis and Cellulomonas pakistanensis, with 98.85% and 98.45% identity, respectively. Phenotypic characterisation and genome sequencing were performed. The isolate was facultative anaerobic, gram-positive, motile, non-spore forming, and rod-shaped. Cell wall fatty acid profiling revealed that 12-methyl-tetradecanoic acid was the most abundant fatty acid (36%). The genome size was 4.25 Mbp with a G + C content of 74.8 mol%. Genomic comparison of species closely related to this strain showed that all digital DNA-DNA hybridisation (dDDH) and mean orthologous nucleotide identity (OrthoANI) values were below published species thresholds (70% and 95-96%, respectively). Based on these data, we conclude that this isolate represents a new bacterial species belonging to the family Cellulomonadaceae and the phylum Actinomycetota. We propose the name Cellulomonas endometrii sp. nov. The type strain is Marseille-Q7820T (= CSUR Q7820 = CECT 30716).

Pregnancy Rates after Hysteroscopic Endometrial Polypectomy versus Endometrial Curettage Polypectomy: A Retrospective Study

Background and Objectives: A relationship between endometrial polypectomy and in vitro fertilization (IVF) pregnancy outcomes has been reported; however, only a few studies have compared polyp removal techniques and pregnancy rates. We investigated whether different polypectomy techniques with endometrial curettage and hysteroscopic polypectomy for endometrial polyps affect subsequent pregnancy outcomes. Materials and Methods: Data from 434 patients who had undergone polypectomy for suspected endometrial polyps using transvaginal ultrasonography before embryo transfer in IVF at four institutions between January 2017 and December 2020 were retrospectively analyzed. Overall, there were 157 and 277 patients in the hysteroscopic (mean age: 35.0 years) and curettage (mean age: 37.3 years) groups, respectively. Single-blastocyst transfer cases were selected from both groups and age-matched to unify background factors. Results: In the single-blastocyst transfer cases, 148 (mean age: 35.0 years) and 196 (mean age: 35.9 years) were in the hysteroscopic and curettage groups, respectively, with the 148 cases matched by age. In these cases, the pregnancy rates for the first embryo transfer were 68.2% (odds ratio (OR): 2.14) and 51.4% (OR: 1.06) in the hysteroscopic and curettage groups, respectively; the resulting OR was 2.03. The pregnancy rates after up to the second transfer were 80.4% (OR: 4.10) and 68.2% (OR: 2.14) in the hysteroscopic and curettage groups, respectively, in which the OR was 1.91. The live birth rates were 66.2% (OR: 1.956) and 53.4% (OR: 1.15) in the hysteroscopic and curettage groups, respectively, in which the odds ratio was 1.71. These results show the effectiveness of hysteroscopic endometrial polypectomy compared to polypectomy with endometrial curettage. No significant difference was found regarding the miscarriage rates between the two groups. Conclusions: Hysteroscopic endometrial polypectomy resulted in a higher pregnancy rate in subsequent embryo transfer than polypectomy with endometrial curettage. Therefore, establishing a facility where polypectomy can be performed hysteroscopically is crucial.

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.

Chronic endometritis: screening, treatment, and pregnancy outcomes in an academic fertility center

PURPOSE

To identify the prevalence of chronic endometritis (CE), compare the efficacy of antibiotic regimens for CE, and examine pregnancy outcomes after treatment for CE among patients in an academic fertility clinic.

METHODS

In this retrospective cohort study, data from patients who underwent endometrial sampling (ES) for CE evaluation at a single academic institution from 2014 to 2020 were collected and analyzed. Rates of CE were compared by indication for ES including recurrent pregnancy loss (RPL), implantation failure (IF), and recent first-trimester pregnancy loss. Treatment and pregnancy outcomes were also evaluated.

RESULTS

Six hundred fifty-three individuals underwent ES to evaluate for CE. The overall prevalence of CE was 28.5%; when stratified by indication, the prevalence of CE was 66.2% for recent first-trimester loss, 27.9% for RPL, and 13.1% for IF (p < .001). Of those with CE, 91.9% received antibiotics, most commonly doxycycline (76.0%). CE clearance was not significantly different when doxycycline was compared to all other regimens (71.3% vs. 58.8%, p = .17), and 68.5% of patients cleared CE after one course of antibiotics. Following two antibiotic courses, CE was cleared in 88.3% of patients. Live birth rates (LBRs) were higher for those with cleared CE compared to patients with untreated CE (34.1% vs. 5.6%, p = .014) and similar for those with cleared CE versus those without CE (34.1% vs. 29.3%, p = .297).

CONCLUSION

CE is common among patients with infertility, particularly those with a recent first-trimester loss. Treatment and clearance of CE were associated with higher LBRs; however, persistent CE was common despite treatment with antibiotics.

Chronic Endometritis and Uterine Endometrium Microbiota in Recurrent Implantation Failure and Recurrent Pregnancy Loss

The aim of this study was to evaluate whether chronic endometritis (CE) and uterine endometrium microbiota were associated with repeated implantation failures (RIFs) and recurrent pregnancy losses (RPLs). In this prospective study, uterine endometrial specimens were obtained from 24 women with RIF, 27 with RPL, and 29 fertile control women. Immunohistochemical staining of CD138 for CE and 16S ribosomal RNA (rRNA) sequencing analysis for uterine endometrium microbiota were performed simultaneously. To assess CE, Liu's method, McQueen scores and plasma cell count/10 mm2 were used. The frequency of CE (plasma cells > 5.15/10 mm2) was higher in women with RPL (29.6%) than in fertile controls (6.8%, p < 0.05). The plasma cell count/10 mm2 in women with RPL (median 1.53, range 0-252.6, p < 0.01) and women with RIF (median 0.6, range 0-6.98, p < 0.05) was higher than in fertile controls (median 0, range 0-29). The uterine endometrium microbiota in women with RPL or RIF was not significantly different from that in fertile controls. However, the relative dominance rate of Lactobacillus iners (median 4.7%, range 0-99.9 vs. median 0%, range 0-100, p < 0.001) and the positive rate of Ureaplasma species (36.3% vs. 8.6%, p < 0.05) were higher in 11 women with CE than in 69 women without CE. The results suggest that CE may be involved in the pathophysiology of RPL and RIF. Lactobacillus iners and Ureaplasma species may be associated with the etiology of CE.

Fertility and pregnancy complications following chorioamnionitis

Acute chorioamnionitis complicates 1-2% of all pregnancies and might increase the prevalence of endometritis that can cause Asherman syndrome or adhesions, but little is known about the direct effects of chorioamnionitis on future fertility. We aimed to evaluate the effect of chorioamnionitis on future fertility and obstetrics complications in patients diagnosed with chorioamnionitis during their pregnancy. We performed an observational, case-control retrospective study of pregnant women aged 18-40 years old, hospitalized with a diagnosis of chorioamnionitis between January 2013 and December 2017. The control group consisted of patients with similar demographic/obstetrics characteristics, matched with a ratio of 1:2 without chorioamnionitis. The prevalence of post gestational diagnostic hysteroscopy was significantly higher in the study group as compared to the control group (22.9% versus 9.0%, respectively; p = 0.005). Moreover, the study group underwent significantly more operative hysteroscopy compared to the control group (10.8% versus 3.6%, respectively; p = 0.04). The patients in the study group had significantly higher prevalence of miscarriages (27% versus 13.2%, respectively; p < 0.01). We conclude that chorioamnionitis may cause endometritis with the consequent impaired fertility, necessitating comprehensive evaluations for secondary infertility, including hysteroscopy aiming to treat intrauterine adhesions that may affect and impair fertility.

The effect of chronic endometritis and treatment on patients with unexplained infertility

PURPOSE

This paper was mainly conducted to investigate the effect of chronic endometritis (CE) on the clinical outcome of patients with unexplained infertility.

MATERIALS AND METHODS

145 patients with unexplained infertility from the Reproductive Center of our hospital from January 2018 to December 2021 were selected as the unexplained infertility group. 42 patients with definite infertility causes were selected as the control group during the same period. Both groups of patients underwent hysteroscopy and immunohistochemical tests for CD38 and CD138. According to the results of hysteroscopy and immunohistochemistry, the incidence of CE between the two groups was analyzed. Patients with CE as CE group accepted oral antibiotic therapy for 14 days. Another 58 patients with unexplained infertility who did not undergo hysteroscopy and immunohistochemical tests for CD38 and CD138 were selected as the unexamined group. Both groups of patients were expected natural pregnancy. Follow-up lasted for 1 year, and the pregnant patients were followed up until delivery.The clinical pregnancy rate, spontaneous abortion rate and baby-carrying home rate of the two groups were compared.

RESULTS

There were 75 patients with CE in the unexplained infertility group, and the prevalence rate was 51.7% (75/145). Compared with the control group (28.6%), the incidence of CE was significantly higher (P < 0.05). After treated with antibiotic treatment, the patients' clinical pregnancy rate was 61.3% (46/75) and baby-carrying home rate was 60% (45/75) in the CE group, which were higher than those in the unexamined group(43.1% & 36.2%) (P < 0.05), while the spontaneous abortion rate was 2.2% (1/46),which was lower than that in the unexamined group (16.0%) (P < 0.05).

CONCLUSIONS

For patients with unexplained infertility, hysteroscopy combined with endometrial immunohistochemical detection of CD38 and CD138 should be performed in time to exclude CE. The clinical pregnancy outcome of CE patients can be significantly improved by antibiotic treatment.

Analysis of the microbiota composition in the genital tract of infertile patients with chronic endometritis or endometrial polyps

Background

The previous researches show that infertile patients have a higher incidence of endometritis and endometrial polyps, and the occurrence of these two diseases is related to changes in the microbiota of the genital tract. We aim to determine the composition and changing characteristics of the microbiota in the genital tract (especially the endometrium) of infertile patients with chronic endometritis or endometrial polyps, and find the correlation between it and the occurrence of diseases.

Methods

This is a prospective study. We collected genital tract biopsy samples from 134 asymptomatic infertile patients receiving assisted reproductive therapy before embryo transfer. Through pathological examination and 16S ribosomal RNA(16S rRNA) sequencing, we determined the distribution of chronic endometritis and endometrial polyps in these patients, as well as their distribution of reproductive tract microorganisms.

Results

Compared with the normal control group, the microbial group of reproductive tract in patients with chronic endometritis and endometrial polyps is changed, and there are significant species differences and relative abundance differences in the vagina, cervix and uterine cavity. Lactobacillus, the dominant flora of female genital tract, showed a change in abundance in patients with endometrial diseases. Endometrial microbiota composed of Staphylococcus, Gardnerella, Atopobium, Streptococcus, Peptostreptococcus, Chlamydia, Fusobacterium, Acinetobacter, etc. are related to chronic endometritis and endometrial polyps.

Conclusion

The results showed that, compared with the normal control group, the endometrial microbiota of infertile patients with chronic endometritis or endometrial polyps did have significant changes in the relative abundance distribution of species, suggesting that changes in local microecology may be an important factor in the occurrence of disease, or even adverse pregnancy outcomes. The further study of endometrial microecology may provide a new opportunity to further improve the diagnosis and treatment strategy of chronic endometritis.