Analysis of the diagnostic value of CD138 for chronic endometritis, the risk factors for the pathogenesis of chronic endometritis and the effect of chronic endometritis on pregnancy: a cohort study

AI-algorithm training and validation for identification of endometrial CD138+ cells in infertility-associated conditions; polycystic ovary syndrome (PCOS) and recurrent implantation failure (RIF)

Background

Endometrial CD138+ plasma cells serve as a diagnostic biomarker for endometrial inflammation, and their elevated occurrence correlates positively with adverse pregnancy outcomes. Infertility-related conditions like polycystic ovary syndrome (PCOS) and recurrent implantation failure (RIF) are closely associated with systemic and local chronic inflammatory status, wherein endometrial CD138+ plasma cell accumulation could also contribute to endometrial pathology. Current methods for quantifying CD138+ cells typically involve laborious and time-consuming microscopic assessments of only a few random areas from a slide. These methods have limitations in accurately representing the entire slide and are susceptible to significant biases arising from intra- and interobserver variations. Implementing artificial intelligence (AI) for CD138+ cell identification could enhance the accuracy, reproducibility, and reliability of analysis.

Methods

Here, an AI algorithm was developed to identify CD138+ plasma cells within endometrial tissue. The AI model comprised two layers of convolutional neural networks (CNNs). CNN1 was trained to segment epithelium and stroma across 28,363 mm2 (2.56 mm2 of epithelium and 24.87 mm2 of stroma), while CNN2 was trained to distinguish stromal cells based on CD138 staining, encompassing 7345 cells in the object layers (6942 CD138- cells and 403 CD138+ cells). The training and performance of the AI model were validated by three experienced pathologists. We collected 193 endometrial tissues from healthy controls (n = 73), women with PCOS (n = 91), and RIF patients (n = 29) and compared the CD138+ cell percentages based on cycle phases, ovulation status, and endometrial receptivity utilizing the AI model.

Results

The AI algorithm consistently and reliably distinguished CD138- and CD138+ cells, with total error rates of 6.32% and 3.23%, respectively. During the training validation, there was a complete agreement between the decisions made by the pathologists and the AI algorithm, while the performance validation demonstrated excellent accuracy between the AI and human evaluation methods (intraclass correlation; 0.76, 95% confidence intervals; 0.36-0.93, p = 0.002) and a positive correlation (Spearman's rank correlation coefficient: 0.79, p < 0.01). In the AI analysis, the AI model revealed higher CD138+ cell percentages in the proliferative phase (PE) endometrium compared to the secretory phase or anovulatory PCOS endometrium, irrespective of PCOS diagnosis. Interestingly, CD138+ percentages differed according to PCOS phenotype in the PE (p = 0.03). On the other hand, the receptivity status had no impact on the cell percentages in RIF samples.

Conclusion

Our findings emphasize the potential and accuracy of the AI algorithm in detecting endometrial CD138+ plasma cells, offering distinct advantages over manual inspection, such as rapid analysis of whole slide images, reduction of intra- and interobserver variations, sparing the valuable time of trained specialists, and consistent productivity. This supports the application of AI technology to help clinical decision-making, for example, in understanding endometrial cycle phase-related dynamics, as well as different reproductive disorders.

Prevalence and confounders of chronic endometritis diagnosed using CD138 in patients with recurrent implantation failure

OBJECTIVE

This retrospective study aimed to investigate the prevalence of chronic endometritis, diagnosed using CD138 immunohistochemistry, among infertile women and to assess the association between chronic endometritis and recurrent implantation failure (RIF).

METHODS

In total, 266 patients who underwent hysteroscopy due to infertility between 2019 and 2020 were included in the analysis. Of these, 136 patients with RIF and 130 non-RIF patients were included in the study. CD138 immunohistochemistry test results, blood biomarkers (including natural killer cells, white blood cells, and the lymphocyte-to-neutrophil ratio), and data on pregnancy outcomes were obtained. If the CD138 test yielded a positive result, the patients received antibiotic treatment.

RESULTS

The overall proportion of CD138-positive patients was 32.7% (87/266). The CD138 positivity rate was not related to the number of cycles with implantation failure. In the RIF patient group, no significant associations were found between CD138 positivity and peripheral blood markers. The clinical pregnancy rates were similar between infertile women treated with antibiotics for chronic endometritis and those without chronic endometritis.

CONCLUSION

To improve the pregnancy rate in infertile patients, it may be helpful to combine CD138 testing with other laboratory tests and administer antibiotic treatment if the result is positive.

Evaluation of Lipopolysaccharide and Interleukin-6 as Useful Screening Tool for Chronic Endometritis

Universal diagnostic criteria for chronic endometritis (CE) have not been established due to differences in study design among researchers and a lack of typical clinical cases. Lipopolysaccharides (LPSs) have been reported to cause inflammation in the reproductive systems of several animals. This study aimed to elucidate the influence of LPS in the pathogenesis of CE in humans. We investigated whether LPS affected cytokine production and cell proliferation in the endometrium using in vivo and in vitro experiments. LPS concentrations were analyzed between control and CE patients using endometrial tissues. LPS administration stimulated the proliferation of EM-E6/E7 cells derived from human endometrial cells. High LPS concentrations were detected in CE patients. LPS concentration was found to correlate with IL-6 gene expression in the endometrium. Inflammation signaling evoked by LPS led to the onset of CE, since LPS stimulates inflammatory responses and cell cycles in the endometrium. We identified LPS and IL-6 as suitable candidate markers for the diagnosis of CE.

Unveiling the Role of Endometrial CD-138: A Comprehensive Review on Its Significance in Infertility and Early Pregnancy

This review comprehensively examines the role of endometrial CD-138 (syndecan-1) in the context of infertility and early pregnancy. The endometrium, a dynamic tissue responsive to hormonal cues, plays a central role in fertility, and understanding the molecular intricacies governing its function is crucial. CD-138, a cell surface proteoglycan, emerges as a critical player expressed by various endometrial cell types. Our exploration encompasses a brief overview of the endometrium, introducing CD-138 as a significant molecular entity. The rationale for the review underscores the importance of elucidating endometrial factors in fertility and addresses existing knowledge gaps related to CD-138. Throughout the review, we unravel the multifaceted nature of CD-138 and its involvement in infertility, highlighting its potential as a diagnostic marker. Furthermore, insights into CD-138's role during early pregnancy, including trophoblast-endothelial interactions, are discussed. In conclusion, the findings underscore the clinical implications of CD-138, suggesting its utility in diagnostics and offering prospects for targeted therapeutic interventions. The identified knowledge gaps propel future research directions, promising to deepen our understanding of this enigmatic molecule and its transformative potential in reproductive medicine.

Gene expression signatures associated with chronic endometritis revealed by RNA sequencing

Introduction

Chronic endometritis (CE) is a persistent inflammatory condition of the endometrium characterized by the infiltration of plasma cells in the endometrial stroma. CD138 immunohistochemistry is considered to improve the CE diagnosis rate.

Methods

Using the number of CD138-positive cells equal or greater than five as a diagnostic criterion for CE, we identified 24 CE and 33 non-CE cases among women with infertility. We conducted RNA-sequencing analysis for these 57 cases in total as an attempt to elucidate the molecular pathogenesis of CE and to search for new biomarkers for CE.

Results and Discussion

By comparing CE and non-CE groups, we identified 20 genes upregulated in the endometria of CE patients, including 12 immunoglobulin-related genes and eight non-immunoglobulin genes as differentially expressed genes. The eight genes were MUC5AC, LTF, CAPN9, MESP1, ACSM1, TVP23A, ALOX15, and MZB1. By analyzing samples in the proliferative and secretory phases of the menstrual cycle separately, we also identified four additional non-immunoglobulin genes upregulated in CE endometria: CCDC13 by comparing the samples in the proliferative phase, and OVGP1, MTUS2, and CLIC6 by comparing the samples in the secretory phase. Although the genes upregulated in CE may serve as novel diagnostic markers of CE, many of them were upregulated only in a limited number of CE cases showing an extremely high number of CD138-positive cells near or over one hundred. Exceptionally, TVP23A was upregulated in the majority of CE cases regardless of the number of CD138-positive cells. The upregulation of TVP23A in the endometria of CE cases may reflect the pathophysiology of a cell-type or cell-types intrinsic to the endometrium rather than the accumulation of plasma cells. Our data, consisting of clinical and transcriptomic information for CE and non-CE cases, helped us identify gene expression signatures associated with CE.

The Role of Plasma Cells as a Marker of Chronic Endometritis: A Systematic Review and Meta-Analysis

Chronic endometritis (CE) is the persistent inflammation of the endometrial lining associated with infertility and various forms of reproductive failures. The diagnosis of CE is based on the histological evidence of stromal plasma cells; however, standardized methods to assess plasma cells are still lacking. In the present paper, we aimed to determine the most appropriate plasma cell threshold to diagnose CE based on pregnancy outcomes. Three electronic databases were searched from their inception to February 2022 for all studies comparing pregnancy outcomes between patients with CE and patients without CE. The relative risk (RR) of pregnancy, miscarriage, and/or live birth rates were calculated and pooled based on the plasma cell threshold adopted. A p-value < 0.05 was considered significant. Nine studies adopting different thresholds (1 to 50 plasma cells/10 HPF) were included. In the meta-analysis, we only found a significant association between miscarriage rate and a plasma cell count ≥ 5/10 HPF (RR = 2.4; p = 0.007). Among studies not suitable for meta-analysis, CE showed an association with worsened pregnancy only when high thresholds (10 and 50/10 HPF) were adopted. In conclusion, our study suggests that the presence of plasma cells at low levels (<5/10 HPF) may not predict worsened pregnancy outcomes. Based on these findings, a threshold of ≥5 plasma cells/10 HPF may be more appropriate to diagnose CE.

Pregnancy outcomes of intrauterine insemination without ovarian stimulation in couples affected by unilateral tubal occlusion and male infertility

BACKGROUND

Information available to date regarding the pregnancy outcomes of intrauterine insemination (IUI) without ovarian stimulation (OS) in infertile patients with unilateral tubal occlusion remains scarce. The objectives of this study were to investigate for couples affected by unilateral tubal occlusion (diagnosed via hysterosalpingography (HSG)/transvaginal real-time three-dimensional hysterosalpingo-contrast sonography (TVS RT-3D-HyCoSy)) and male infertility: (1) whether significant differences exist in pregnancy outcomes between IUI with or without OS cycles, and (2) whether the pregnancy outcomes of IUI without OS in women with unilateral tubal occlusion were similar to those of women with bilateral patent tubes.

METHODS

258 couples affected by male infertility completed 399 IUI cycles. The cycles were divided into three groups: group A, IUI without OS in women with unilateral tubal occlusion; group B, IUI with OS in women with unilateral tubal occlusion; and group C, IUI without OS in women with bilateral patent tubes. The main outcome measures, including clinical pregnancy rate (CPR), live birth rate (LBR), and first trimester miscarriage rate, were compared between either groups A and B or groups A and C.

RESULTS

Although the number of dominant follicles > 16 mm were significantly higher in group B than that in group A (group B vs. group A: 1.6 ± 0.6 vs. 1.0 ± 0.2, P < 0.001), the CPR, LBR, and first trimester miscarriage rate were comparable between these two groups. When comparing group C to group A, the duration of infertility was significantly longer in group C than that in group A (group A vs. group C: 2.3 ± 1.2 (year) vs. 2.9 ± 2.1 (year), P = 0.017). Except for the first trimester miscarriage rate, which was significantly higher in group A (42.9%, 3/7) than that in group C (7.1%, 2/28) (P = 0.044), no significant differences were observed in the CPR and LBR in these two groups. After adjusting for female age, body mass index, and the duration of infertility, similar results were obtained between groups A and C.

CONCLUSIONS

In couples affected by unilateral tubal occlusion (diagnosed via HSG/TVS RT-3D-HyCoSy) and male infertility, IUI without OS might be an alternative treatment strategy. However, when compared to patients with bilateral patent tubes, the patients with unilateral tubal occlusion showed a higher first trimester miscarriage rate following IUI without OS cycles. Further studies are warranted to clarify this relationship.

Follicular helper T lymphocytes in the endometria of patients with reproductive failure: Association with pregnancy outcomes and inflammatory status of the endometria

PROBLEM

The phenotypes and functions of B and CD4⁺ T-helper cell subsets during chronic inflammation of the endometria remain largely unexplored. This study aimed to investigate the characteristics and functions of follicular helper T (Tfh) cells to understand the pathological mechanisms of chronic endometritis (CE).

METHOD OF STUDY

Eighty patients who underwent hysteroscopic and histopathological examinations for CE were divided into three groups-those with positive results for hysteroscopy and CD138 staining (DP), negative results for hysteroscopy but positive CD138 staining (SP), and negative results for hysteroscopy and CD138 staining (DN). The phenotypes of B cells and CD4⁺ T-cell subsets were analyzed using flow cytometry.

RESULTS

CD38⁺ and CD138⁺ cells were mainly expressed in the non-leukocyte population of the endometria, and the endometrial CD19⁺ CD138⁺ B cells were fewer than the CD3⁺ CD138⁺ T cells. The percentage of Tfh cells increased with chronic inflammation in the endometria. Additionally, the elevated percentage of Tfh cells correlated with the number of miscarriages.

CONCLUSIONS

CD4⁺ T cells, particularly Tfh cells, may be critical in chronic endometrial inflammation and affect its microenvironment, thereby regulating endometrial receptivity, compared to B cells.

Adverse impact of CD138+ cells in proliferative-phase endometrium on pregnancy outcomes in fresh IVF/ICSI cycles

To evaluate the impact of Syndecan-1 (CD138) in proliferative-phase endometrium on pregnancy outcomes in fresh in vitro fertilization (IVF)/ intracytoplasmic sperm injection (ICSI) cycles. This retrospective cohort study contained 273 patients who underwent IVF/ICSI with fresh embryo transfer following an endometrial curettage from January 2020 to May 2022. Endometrial curettage was performed on all patients within 3 to 5 days following menstruation and endometrial tissue was acquired for detection of plasma cells by immunohistochemistry. Subsequent pregnancy outcomes of all cycles were traced and analyzed. A total of 149 patients became pregnant (i.e., pregnant group) in the fresh transfer IVF/ICSI cycles and 124 did not become pregnant (i.e., nonpregnant group). The number of CD138 + cells/ high-power field (HPF) of the nonpregnant group was significantly higher than the pregnant group (2.36 ± 4.24 vs 1.31 ± 3.41, P = .008). The cut off value of CD138 + cells/HPF was 2 by receiver operating characteristic curve analysis, with an area under the receiver operating characteristic curve of 0.572. Compared with the negative group (i.e., CD138 + cells/HPF < 2, n = 204), the positive group (i.e., CD138 + cells/HPF ≥ 2, n = 69) had a significantly lower clinical pregnancy rate (71.8% vs 40.6%, P < .001). The clinical pregnancy rate revealed a gradually decreasing trend with the increase in CD138 + cells. Proliferative-phase endometrial CD138 + cells may be an adverse indicator for pregnancy outcomes in fresh IVF/ICSI cycles, with a certain value in predicting non-pregnancy. Pregnancy outcome was poor when CD138 + cells/HPF ≥ 2 in the endometrium and may worsen with the increase in CD138 + cells.

Chronic poor healing wounds of post cesarean scar diverticulum: Altered angiogenesis and immunobiology

Cesarean section (CS) scar diverticula (CSD) is an important cause impede further fecundity, with rather complicated pathophysiologic mechanisms and unclear etiopathogenesis. In this study, we detect the influences of CSD on the pregnancy outcomes in in-vitro fertilization (IVF) or intra-cytoplasmic sperm injection (ICSI) embryo transfer (ET) cycles, and further explore the mechanisms involved based on histopathology and immunology differences in endometrium between CSD and vaginal birth (VB) women. The CS group had significantly lower CLBR compared to NCS group. Histopathological analysis showed that the higher prevalent of CE is accompanied by excessive fibroblast proliferation at the lower segment of uterus and significantly exaggerated vascular proliferation in situ. Intrauterine inflammatory cytokines including IL-1α, IL-1β, IL-6, IL-8, TNF-α and SDF-1α were also increased in CSD group. The present data suggests impaired fecundity in CSD women undergoing IVF/ICSI treatment. Although the causal relationship is ambiguous, the potential mechanisms may involve persistent inflammatory response in the uterine cavity, active vascular proliferation accompanied with increased fibrosis which are responsible for poor chronic wound healing of CSD.

Chronic endometritis increases the recurrence of endometrial polyps in premenopausal women after hysteroscopic polypectomy

BACKGROUND

The reported recurrence rate of endometrial polyps (EPs) after hysteroscopic polypectomy varied widely, and the factors influencing the recurrence of EPs are still controversial. Furthermore, the known definite independent risk factors are almost unchangeable, such as the number of EPs and previous polypectomy history. The aim of this study was to evaluate the impact of chronic endometritis (CE) on the recurrence of EPs in premenopausal women who underwent hysteroscopic polypectomy.

METHODS

A retrospective study was conducted at a university-affiliated hospital. Premenopausal women who underwent hysteroscopic polypectomy were enrolled, and those with definite confounding factors for polyp recurrence were excluded, including endometriosis and previous polypectomy history. A total of 233 women were enrolled in this study, including 64 (27.5%) cases with CE and 169 (72.5%) cases without CE. CE was diagnosed via immunohistochemical detection of CD138 on the endometrial specimen. Comparison of the recurrence rate of EPs was performed in women with or without CE at each monitoring stage (i.e., at 3, 6, 9 and 12 months) after hysteroscopic polypectomy.

RESULTS

The recurrence rates of EPs at one year in patients with and without CE were 26.6% (95% confidence interval [CI] 15.8-37.4%) and 9.5% (95% CI 5.0-14.0%), respectively, with an overall recurrence rate of 14.2% (95% CI 9.7-18.7%). The hazard ratio (HR) for EPs recurrence in the EPs with CE cohort versus the EPs without CE cohort was 3.08 (95% CI 1.56-6.09) (P = 0.001). Similarly, the recurrence rate of EPs was significantly higher in women with CE than in those without CE at each monitoring stage (i.e., 3, 6 and 9 months). CE and multiple EPs were risk factors for EPs recurrence. The HR for EPs recurrence in the EPs with CE cohort compared with the EPs without CE cohort was 3.06, after adjustment for the number of EPs.

CONCLUSIONS

CE was a harmful factor for the recurrence of EPs in premenopausal women after hysteroscopic polypectomy. Thus, routine screening for CE during hysteroscopic polypectomy was needed. Frequent monitoring was needed for multiple EPs as the number of EPs also contributed to polyp recurrence.

An injectable hydrogel scaffold with IL-1β-activated MSC-derived exosomes for the treatment of endometritis

Chronic endometritis is a common gynecological disease resulting from various long-term recurrent infections, and is closely related to myositis, miscarriage, and even infertility. There is still no satisfactory treatment method currently in clinical therapy. Mesenchymal stem cell (MSC)-derived exosomes, an important kind of paracrine product, have been used to treat inflammatory diseases due to their promising immunomodulatory function and tissue repair ability similar to MSCs. Considering that the exosome contents and functions are regulated by the MSC status and the MSC status is significantly influenced by its surrounding microenvironment, we propose a hypothesis that exosomes derived from inflammation-simulated MSCs will possess stronger inhibition ability for inflammation. Herein, we used IL-1β to activate rat bone MSCs for obtaining β-exo and constructed an injectable polypeptide hydrogel scaffold by loading β-exo (β-exo@pep) for an in situ slow release of β-exo. The results showed that the polypeptide hydrogel can provide a sustained release of exosomes in 14 days. The β-exo@pep composite hydrogel can more effectively inhibit the production of inflammatory factors such as TNF-α, IL-1β, and IFN-γ, while it can promote the production of anti-inflammatory factors such as Arg-1, IL-6, and IL-10. The β-exo@pep composite hydrogel significantly promoted cell migration, invasion, and vessel tube formation in vitro. The experiments in a rat model of endometritis proved that the β-exo@pep composite scaffold possessed excellent ability towards anti-inflammation and endometrial regeneration. The research studies on the molecular mechanism revealed that the protein expressions of HMGB1 and phosphorylated IKB-α and p65 are down-regulated in the cells treated with β-exo@pep, indicating the involvement of the NF-κB signaling pathway. This study provides an effective method for the treatment of chronic endometritis, which is promising for clinical use.

The alteration of intrauterine microbiota in chronic endometritis patients based on 16S rRNA sequencing analysis

BACKGROUND

Chronic endometritis (CE) is a disease of continuous and subtle inflammation occurring in the endometrial stromal area, which is often asymptomatic or present with non-specific clinical symptoms.

METHODS

This study investigated the composition and distribution of the intrauterine microbiota of 71 patients who underwent hysteroscopy during the routine clinical inspection of infertility. Among them, patients who were diagnosed with chronic endometritis (CE) were allocated into CE group (n = 29) and others into non-CE group (n = 42). There was no significant difference in average age between the two groups (P = 0.19). Uterine flushing fluid was collected by the self-developed cervical trocar uterine cavity sampler and 16S rRNA sequencing was performed.

RESULTS

The alpha diversity in the CE group was significantly higher than that in the non-CE group (P < 0.05). Firmicutes (newly named Bacillota) were the dominant phylum in the non-CE group (72.23%), while their abundance was much lower in the CE group (49.92%), but there was no statistically significant difference between the two groups. The abundances of Actinobacteriota and Cyanobacteria in the CE group were significantly higher than those in the non-CE group (P < 0.05). At the genus level, the abundance of Lactobacillus dominated in all samples, which presented a significantly lower abundance in the CE group (40.88%) than that in the non-CE group (64.22%) (P < 0.05). Correspondingly, the abundance of non-Lactobacillus was higher in the CE group, among which Pseudomonas and Cutibacterium increased significantly (P < 0.01). Moreover, compared with the non-CE group, the pathways involved in arginine and proline metabolism and retinol metabolism were significantly enriched in the CE group (P < 0.05), while the metabolism of lipid and prenyltransferases were significantly decreased in the CE group (P < 0.05).

CONCLUSIONS

A certain microbial community was colonized in the uterine cavity, which was dominated by Lactobacillus. The structure and distribution of intrauterine microbiota in the CE group were different from those in the non-CE group by showing a lower abundance of Lactobacillus, and a significantly higher abundance of Pseudomonas and Cutibacterium. Additionally, the microbial metabolism was altered in the CE group. This study elaborated the alteration of intrauterine microbiota in CE patients, which may contribute to the diagnosis of CE and provide a reference for antibiotic treatment of CE.

The Correlation between Chronic Endometritis and Tubal-Factor Infertility

OBJECTIVE

To identify the prevalence and risk factors for chronic endometritis (CE) with tubal factors and the correlation between chronic endometritis and tubal factors among infertile populations.

METHOD

A total of 52 patients with chronic endometritis (CE group) who underwent laparoscopy and hysteroscopic surgery were recruited between July 2020 and December 2021. A total of 38 patients without chronic endometritis (non-CE group) were included as a control. Patients with endometriosis and intra-uterine abnormalities were excluded. Endometrial samples were collected during surgery for CD138 immunohistochemistry staining for the diagnosis of CE. Preoperative information (including age, reproductive health characteristics, previous medical and surgical history), intra-operative information (including the patency of the fallopian tube, the presence of hydrosalpinx, score and the grade of tubal lesion condition) and post-operative information (counts of CD138-positive HPF in the endometrial specimen) were collected.

RESULT

A multivariate analysis revealed that tubal factors with unilateral or bilateral occlusion were significantly higher in the CE group (OR 3.066, 95% CI 1.020-9.213, p = 0.046). The bilateral occlusion of fallopian tubes (OR 8.785, 95% CI 1.408-54.818, p = 0.020) rather than unilateral occlusion (OR 2.860, 95% CI 0.893-9.162, p = 0.077) was significantly associated with chronic endometritis. The presence of a hydrosalpinx on one side (OR 7.842, 95% CI 1.279-48.086, p = 0.026) or both sides (OR 9.450, 95% CI 1.037-86.148, p = 0.046) was significantly associated with chronic endometritis. The comparison of CD138-positive HPF counts among the tubal occlusion patients without hydrosalpinx, patients with unilateral hydrosalpinx and patients with bilateral hydrosalpinx were as follows: 1 HPF (50.00% vs. 12.50% vs. 11.11%, p = 0.051), 2 HPF (38.89% vs. 25.00% vs. 22.22%, p = 0.615), ≥3 HPF (11.11% vs. 62.50% vs. 66.67%, p = 0.005). The stage of tubal condition was positively correlated with CD138-positive HPF counts in women with chronic endometritis (r = 0.460, p = 0.001).

CONCLUSION

CE was closely related to the blockage of fallopian tubes and hydrosalpinx. The severity degree of the fallopian lesion condition was associated with inflammation of the endometrium.

Higher Prevalence of Chronic Endometritis in Women with Cesarean Scar Defect: A Retrospective Study Using Propensity Score Matching

(1) Background: A cesarean scar defect may cause localized inflammation of the endometrial tissue, and various researchers believe that the presence of a cesarean scar defect is associated with chronic endometritis. However, there is no report on the possible association between cesarean scar defects and chronic endometritis thus far. This study aimed to assess the role of having a cesarean scar defect in a person's susceptibility to chronic endometritis. (2) Methods: This retrospective propensity-score-matched study comprised 1411 patients with chronic endometritis that were admitted to Henan Provincial People's Hospital in China from 2020 to 2022. Based on whether a cesarean scar defect was present or not, all cases were assigned to the cesarean scar defect group or the control group. (3) Results: Of the 1411 patients, 331 patients with a cesarean scar defect were matched to 170 controls. All unbalanced covariates between groups were balanced after matching. Before matching, the prevalence of chronic endometritis in the cesarean scar defect group and in the control group was 28.8% and 19.6%, respectively. After correcting for all confounding factors, a logistic regression analysis showed that cesarean scar defect occurrence may increase the risk of chronic endometritis (odds ratio (OR), 1.766; 95% confidence interval (CI), 1.217-2.563; p = 0.003). After matching, the prevalence of chronic endometritis was 28.8% in the cesarean scar defect group and 20.5% in the control group. Thus, even after correcting for all confounding factors, the logistic regression analysis still showed that a cesarean scar defect remained an independent risk factor for chronic endometritis prevalence (OR, 1.571; 95% CI, 1.021-2.418; p = 0.040). The findings were consistent throughout the sensitivity analyses. (4) Conclusions: The present results suggest that the onset of a cesarean scar defect may increase the risk of chronic endometritis.

Association between hysteroscopic features of chronic endometritis and pregnancy outcomes of patients after in vitro fertilization: a retrospective cohort study

This retrospective cohort study explored the morphological features of chronic endometritis (CE) and pregnancy outcomes during in vitro fertilization (IVF) in women with CE (429) at Yantai Yuhuangding Hospital between January 2017 and September 2018. The primary outcome was the clinical pregnancy rate (CPR). The women displayed haemorrhagic spots (175), hyperaemia (122), micropolyps (75), hyperaemia combined with micropolyps (49) and others (8). The CPR and live birth rate (LBR) were different among the hysteroscopic features of CE in fresh embryo transfer cycles (p = .002, p = .011). The miscarriage and premature birth rates were not significantly different among groups (p > .05). Hyperaemia (0.47 [95% CI, 0.29; 0.77]), micropolyps (0.40 [95% CI, 0.23; 0.72]), hyperaemia combined with micropolyps (0.35 [95% CI, 0.18; 0.69]) and others (0.36 [95% CI, 0.19; 0.69]) were associated with the CPR. In conclusion, the hysteroscopic features of CE are associated with IVF pregnancy outcomes, and there were differences in pregnancy outcomes with different CE hysteroscopic features.IMPACT STATEMENTWhat is already known on this subject? Chronic endometritis (CE) is associated with adverse pregnancy outcomes such as infertility, premature delivery and miscarriage. CE can reduce the success rate of pregnancy and even lead to obstetric and neonatal complications, and is an adverse factor for the success of in vitro fertilization (IVF). There are different types of CE, but their impact on IVF outcomes is unknown.What the results of this study add? The CPR and LBR were different among the hysteroscopic features of CE in fresh embryo transfer cycles (p = .002, p = .011). The miscarriage and premature birth rates were not significantly different among groups (p > .05). After adjustment, the multivariable analysis showed that hyperaemia (OR = 0.47, p = .002), micropolyps (OR = 0.40, p = .002), hyperaemia combined with micropolyps (OR = 0.35, p = .002) and others (OR = 0.36, p = .002) were associated with the CPR among patients with CE.What the implications are of these findings for clinical practice and/or further research? The hysteroscopic features of CE are associated with IVF pregnancy outcomes, and there were differences in pregnancy outcomes with different CE hysteroscopic features. Hence, women with repeated IVF failure should undergo hysteroscopy to examine for the presence of CE and its nature.

The menstrual cycle phase impacts the detection of plasma cells and the diagnosis of chronic endometritis in endometrial biopsy specimens

OBJECTIVE

To assess the impact of menstrual cycle phase on the detection of plasma cells.

DESIGN

A retrospective cohort study.

SETTING

Fertility clinic.

PATIENT(S)

Biopsies from 157 patients met criteria for inclusion, 91 in the follicular phase and 60 in the luteal phase. Patient groups were similar in body mass index and number of previous live births; however, differed in terms of age, infertility history, and biopsy indication.

INTERVENTIONS

Endometrial biopsies from patients at a fertility clinic from 2018-2020 were retrospectively reviewed. Biopsies were excluded if patients had a previous chronic endometritis diagnosis, abnormal uterine cavity or were on hormone therapy. Each case was reviewed by a gynecologic pathologist for plasma cells by hematoxylin and eosin and CD138 staining. Demographic and clinical data were collected. Continuous variables were compared using Welch t test and Wilcoxon's rank sum test, and categorical variables using Pearson's χ² test. Logistic regression was used to calculate odds ratio and 95% confidence intervals for the association between the presence of plasma cells and cycle phase. Multinomial logistic regression was used to estimate the odds ratios for nominal outcomes. Pathology reports were reviewed. Plasma cell enumeration using hematoxylin and eosin-stained sections and CD138 immunohistochemical stains (performed at the time of biopsy by a gynecologic pathologist) was recorded.

MAIN OUTCOME MEASURE(S)

Presence and density of plasma cells.

RESULT(S)

We found a higher likelihood of finding plasma cells in the follicular than in luteal phase (59.3% vs. 19.7%). There was a higher likelihood of finding plasma cells in the early (cycle days 5-8, 29 cases or 76.3% of cases with plasma cells) than in the late follicular phase (cycle days 9-14, 25 cases or 47.2%). There was a higher density of plasma cells in the follicular phase group than in the luteal phase group (25.3% vs. 1.5% scattered and 13.2% vs. 0 clusters).

CONCLUSION(S)

Plasma cells are more likely to be present during the follicular phase compared with the luteal phase and in the early compared with the late follicular phase. Further studies are needed to identify the optimal timing of biopsy to standardize the diagnosis.

Diagnosing chronic endometritis: when simplification fails to clarify

Reproductive immunology has grown in importance in recent years and has even developed into a discipline of its own within the field of reproductive medicine. Many aspects of reproductive failure such as repeated implantation failure or recurrent miscarriages are, meanwhile, seen as a consequence of aberrant expression of immunological factors. This is reflected by the increasing number of tests for assessing and quantifying different immune cell types as well as by a wide range of immune therapies offered to a clientele consisting of desperate patients requesting additional ‘IVF tools’: first, what is still usually disregarded is the enormous plasticity and fluctuation of most immune cells in the genital tract; second, their still poorly characterized functions in the endometrial cycle: further, their partially unknown role in embryo implantation and in establishing a pregnancy; and third, the fact that one of the fundamental hypotheses of reproductive immunology—of note—the Medawar concept or ‘Medawar's Paradox’ of semi-allogeneic graft embryo, is partially based on an erroneous assumption, i.e. the immunologic rejection and tolerance of an embryo. In the present opinion article, we comment on the diagnostic procedures and therapy approaches for chronic endometritis within the scope of reproductive medicine.

Sonoelastography evaluation in the diagnosis of endometrial pathology combined with chronic endometritis in infertile women

Endometrial pathology, including hyperplastic processes in the structure of reproductive disorders, occupies one of the leading places along with inflammatory diseases of the pelvic organs, contributing to infertility in 80% of cases and irregular menstrual cycle in 40-43%. This study aims to optimize the diagnostic algorithm in patients with endometrial hyperplasia combined with chronic endometritis and determine qualitative indicators of compression sonoelastography in patients with endometrial pathology and infertility. A comprehensive clinical and laboratory examination of 90 infertile patients aged 25 to 45 years with endometrial hyperplasia combined with chronic inflammation, retention cysts, and benign ovarian tumors was carried out. The results of clinical-laboratory and complex ultrasound examination with compression sonoelastography were compared with the data of pathomorphological and immunohistochemical studies. A high percentage of pelvic inflammatory disease (55.0%), benign lesions of the cervix (67.5%), hyperplastic processes of the myometrium (37.5%), an increasing number of polyps by 2.9 times, leiomyomas and adenomyosis - by 2.3 times (p<0.05) was established. In the case of a combination of endometrial hyperplasia and ovarian cysts, a high percentage of comorbidity of gynecological pathology is verified (37.8%), and the use of compression sonoelastography allows to establish class II and class III elastograms in 91.1% of cases which characterize benign endometrial lesions, reduce the number of false-positive results in 95.6% of cases, correctly interpret the nature of pathological changes and increase the sensitivity of ultrasound techniques.

The role of endometrial staining for CD138 as a marker of chronic endometritis in predicting live birth

PURPOSE

Chronic endometritis (CE) is diagnosed via endometrial biopsy and staining for plasma cells. A threshold plasma cell count that identifies CE and predicts pregnancy outcomes has not been established, and the prevalence of plasma cells in the general infertile population is unknown. The purpose of this study was to determine the prevalence of plasma cells in the general infertile population and whether a threshold exists which predicts live birth.

METHODS

Endometrial samples were obtained prospectively from 80 women undergoing IVF, embedded in paraffin, and stained for plasma cells using mouse mono-clonal antibody for CD138. Slides were reviewed at 20× magnification and 10 random images captured. Three reviewers graded each image for plasma cells. Participants underwent single, euploid, and frozen blastocyst transfer.

RESULTS

Forty-nine percent of samples had ≥1 plasma cell across 10 HPFs, 11% had ≥5 cells across 10 HPFs, and 4% had ≥10 cells across 10 HPFs. There was no difference in prevalence between those who did and did not achieve live birth. Using thresholds of 1, 5, and 10 plasma cells per 10 HPFs, there were no differences in implantation, clinical pregnancy, clinical pregnancy loss, or live birth rates between patients with and without CE.

CONCLUSION

Endometrial plasma cells are present in half the general infertile population and do not predict implantation, clinical pregnancy, clinical pregnancy loss, or live birth rates at low levels.

MUM-1 immunohistochemistry has high accuracy and reliability in the diagnosis of chronic endometritis: a multi-centre comparative study with CD-138 immunostaining

PURPOSE

The current gold standard for chronic endometritis (CE) diagnosis is immunohistochemistry (IHC) for CD-138. However, IHC for CD-138 is not exempt from diagnostic limitations. The aim of our study was to evaluate the reliability and accuracy of MUM-1 IHC, as compared with CD-138.

METHODS

This is a multi-centre, retrospective, observational study, which included three tertiary hysteroscopic centres in university teaching hospitals. One hundred ninety-three consecutive women of reproductive age were referred to our hysteroscopy services due to infertility, recurrent miscarriage, abnormal uterine bleeding, endometrial polyps or myomas. All women underwent hysteroscopy plus endometrial biopsy. Endometrial samples were analysed through histology, CD138 and MUM-1 IHC. The primary outcome was to evaluate the diagnostic accuracy of MUM-1 IHC for CE, as compared with CD-138 IHC.

RESULTS

Sensitivity and specificity of CD-138 and MUM-1 IHC were respectively 89.13%, 79.59% versus 93.48% and 85.03%. The overall diagnostic accuracy of MUM-1 and CD-138 IHC were similar (AUC = 0.893 vs AUC = 0.844). The intercorrelation coefficient for single measurements was high between the two techniques (ICC = 0.831, 0.761-0.881 95%CI). However, among CE positive women, MUM-1 allowed the identification of higher number of plasma cells/hpf than CD-138 (6.50 [SD 4.80] vs 5.05 [SD 3.37]; p = 0.017). Additionally, MUM-1 showed a higher inter-observer agreement as compared to CD-138.

CONCLUSION

IHC for MUM-1 and CD-138 showed a similar accuracy for detecting endometrial stromal plasma cells. Notably, MUM-1 showed higher reliability in the paired comparison of the individual samples than CD-138. Thus, MUM-1 may represent a novel, promising add-on technique for the diagnosis of CE.

Correlation between hysteroscopy findings in patients with hydrosalpinx and chronic endometritis

OBJECTIVE

To evaluate the role of hydrosalpinx in susceptibility to chronic endometritis (CE).

METHODS

This is a retrospective cohort study, which includes 624 patients with hydrosalpinx (group A) and 789 patients without hydrosalpinx (group B) undergoing laparoscopy and hysteroscopy simultaneously. Endometrial morphology was recorded under hysteroscopy. Endometrial biopsy was obtained after hysteroscopy, and immunohistochemical staining for syndecan-1 (CD138) was carried out.

RESULTS

No significantly statistical differences were found between the two groups when comparing the incidence of endometrial hyperemia or endometrial micro-polyps under hysteroscopy (P > 0.05). Hydrosalpinx had a significant impact on the incidence of CE (P < 0.05) (plasma cell count: no plasma cells: odds ratio [OR] 0.71, 95% confidence interval [CI] 0.58-0.88, P = 0.002; ≥1/high-power field [HPF]: OR 1.40, 95% CI 1.14-1.74, P = 0.002; ≥3/HPF: OR 1.50, 95% CI 1.18-1.91, P = 0.001; ≥5/HPF: OR 1.62, 95% CI 1.27-2.21, P < 0.001). There were no significant differences in the comparison of plasma cell count between the unilateral hydrosalpinx group (274 patients) and the bilateral hydrosalpinx group (350 patients) (P > 0.05).

CONCLUSION

The presence of hydrosalpinx increased the incidence of CE. Bilateral hydrosalpinx did not significantly increase the incidence of CE compared with unilateral hydrosalpinx.

Treatment following hysteroscopy and endometrial diagnostic biopsy increases the chance for live birth in women with chronic endometritis

Problem

Repeated implantation failure and recurrent pregnancy loss are associated with chronic endometritis, a persistent endometrial inflammation. Its diagnosis and treatment may increase pregnancy and live birth rates. The aim of this study was to assess the effectiveness of endometrial diagnostic biopsy and subsequent antibiotic treatment in cases of chronic endometritis on reproductive outcomes over a long observation period.

Method of Study

We conducted a historical cohort study (2014–2018) at our University‐based infertility center that included women (n = 108) with repeated implantation failure or recurrent pregnancy loss without known pathologies associated with either condition. Forty‐one women underwent a hysteroscopy only (reference group); the remaining 67 women underwent, in addition to the hysteroscopy, an endometrial diagnostic biopsy with immunohistochemically staining for CD138 to detect plasma cells (biopsy group). If one or more plasma cells were detected, the women were treated with doxycycline 100 mg twice a day orally for 2 weeks. We performed stratified survival analysis (Kaplan‐Meier) and Cox regression.

Results

The biopsy group had higher chances of pregnancy (hazard ratio 2.28; 95% confidence interval 1.23–4.24; p = .009) and of live birth (hazard ratio 2.76; 95% confidence interval 1.30–5.87; p = .008) compared with the reference group. In the sensitivity analysis, repeated implantation failure or recurrent pregnancy loss did not affect the outcome.

Conclusion

Endometrial diagnostic biopsy followed by antibiotic treatment in case of chronic endometritis in women with repeated implantation failure or recurrent pregnancy loss may increase the chances for live birth.

Redefining chronic endometritis: the importance of endometrial stromal changes

OBJECTIVE

To develop diagnostic criteria for chronic endometritis and compare the prevalence of chronic endometritis between women with recurrent pregnancy loss (RPL) and controls.

DESIGN

Cohort study.

SETTING

Single academic fertility center.

PATIENTS

Women with unexplained RPL (two or more pregnancy losses) and prospectively recruited controls without a history of RPL or infertility.

INTERVENTIONS

Endometrial samples were stained with hematoxylin and eosin and CD138. A pathologist blinded to patient history recorded the number of plasma cells per 10 high-power fields (HPFs). In addition, the presence or absence of endometrial stromal changes was documented.

MAIN OUTCOME MEASURE

Prevalence of chronic endometritis.

RESULTS

Endometrial samples from 50 women with unexplained RPL and 26 controls were evaluated. When chronic endometritis was defined as the presence of one or more plasma cells per 10 HPFs, 31% of controls and 56% of women with RPL met the criterion. When both endometrial stromal changes and plasma cells were required for a diagnosis of chronic endometritis, no controls and 30% of women with RPL met the criteria.

CONCLUSIONS

Although rare plasma cells were found in biopsy samples from controls, the presence of both plasma cells and endometrial stromal changes was limited to the RPL cohort. We propose that chronic endometritis be defined as the presence of one or more plasma cells per 10 HPFs in the setting of endometrial stromal changes. With the use of these strict diagnostic criteria, women with RPL have a significantly higher rate of chronic endometritis, supporting an association between chronic endometritis and RPL.

Characterization of the vaginal and endometrial microbiome in patients with chronic endometritis

OBJECTIVE

To compare the endometrial and vaginal microbiome of women with and without chronic endometritis.

STUDY DESIGN

A cohort study with 60 patients undergoing assisted reproductive treatment with their own or donated gametes was undertaken. Vaginal and endometrial samples were taken in the cycle prior to embryo transfer. The endometrial and vaginal microbiome was analysed by mass sequencing of the V3V4 region of 16S rRNA gene. Bioinformatics analysis was performed using QIIME2 and MicrobiomeAnalyst packages. Alpha diversity, beta diversity and taxonomic characterization were compared between samples that tested positive and negative for chronic endometritis on CD138 immunohistochemistry.

RESULTS

Different bacterial communities were detected when vaginal and endometrial samples were analysed in patients with and without endometritis diagnosed using CD138 immunohistochemistry. In patients with endometritis, a higher alpha-diversity index was found in vaginal samples (p = 0.15 for the Shannon index) and significant differences were found in endometrial samples (p = 0.01 for the Shannon index). In the beta-diversity analysis, no significant differences were observed between the groups with and without endometritis. Vaginal and endometrial samples from women with endometritis showed a microbiome pattern that was not dominated by Lactobacillus spp. Relative abundance analysis identified Ralstonia and Gardnerella spp. in endometrial samples, and Streptoccoccus and Ureaplasma spp. in vaginal samples of patients diagnosed with chronic endometritis on CD138 immunohistochemistry. When comparing endometrial and vaginal samples diagnosed with endometritis on CD138 immunohistochemistry, both alpha diversity (p = 0.06 for the Shannon index and p = 0.08 for the Simpson index) and beta diversity (p < 0.001) showed significant differences. Lactobacillus spp. (p = 3.76E-4), Ralstonia spp. (p = 8.19E-4), Delftia spp. (p = 0.004) and Anaerobacillus spp. (p = 0.004) were identified in these sample groups.

CONCLUSION

These results demonstrate the existence of a characteristic vaginal and endometrial microbiota in patients with chronic endometritis. Different genera and species were identified in patients with and without chronic endometritis depending on whether the sample was endometrial or vaginal. There is a clear relationship between changes in the vaginal microbiome and chronic endometritis. The microbiota is a continuum throughout the female reproductive tract, so study of the vaginal microbiota could be useful for the diagnosis of diseases of the upper reproductive tract, such as chronic endometritis.

Is Chronic Endometritis Associated with Tubal Infertility? A Prospective Cohort Study

STUDY OBJECTIVE

Chronic endometritis (CE), which often presents asymptomatically, is associated with recurrent pregnancy loss, recurrent implantation failure after in vitro fertilization, and endometriosis. Data connecting CE with fallopian tubal occlusion are limited. The aim was to assess a potential association of CE, defined by the presence of syndecan-1 (CD138)-positive plasma cells in endometrial tissue samples, with fallopian tube patency and other factors for infertility, including endometriosis, adenomyosis, and hydrosalpinges.

DESIGN

Prospective, monocentral pilot study.

SETTING

Tertiary care center.

PATIENTS

A cohort of 100 women who were infertile was enrolled from July 2019 to December 2020.

INTERVENTIONS

Hysteroscopy with endometrial biopsy and laparoscopy with chromopertubation.

MEASUREMENTS AND MAIN RESULTS

CE was found in 13 women (13.0%) and was associated with endometriosis (p = .034) and unilateral/bilateral fallopian tube blockage (p = .013). In women with endometriosis, the mean number of CD138-positive cells was positively correlated with the revised American Society for Reproductive Medicine score (r = .302, p = .028). In a binary regression model, the presence of a hydrosalpinx on one or both sides (odds ratio 15.308; 95% confidence interval, 1.637-143.189; p = .017) and the finding of CE in the endometrial tissue sample (odds ratio 5.273; 95% confidence interval, 1.257-22.116; p = .023) were significantly associated with fallopian tubal occlusion.

CONCLUSION

CE was significantly associated with blockage of the fallopian tubes and endometriosis. Endometriosis stage was associated with the number of CD138-positive cells in endometrial biopsies.

Immunological Risk Factors in Recurrent Pregnancy Loss: Guidelines Versus Current State of the Art

Around 1-5% of all couples experience recurrent pregnancy loss (RPL). Established risk factors include anatomical, genetic, endocrine, and hemostatic alterations. With around 50% of idiopathic cases, immunological risk factors are getting into the scientific focus, however international guidelines hardly take them into account. Within this review, the current state of immunological risk factors in RPL in international guidelines of the European Society of Reproduction and Embryology (ESHRE), American Society of Reproductive Medicine (ASRM), German/Austrian/Swiss Society of Obstetrics and Gynecology (DGGG/OEGGG/SGGG) and the Royal College of Obstetricians and Gynecologists (RCOG) are evaluated. Special attention was drawn to recommendations in the guidelines regarding diagnostic factors such as autoantibodies, natural killer cells, regulatory T cells, dendritic cells, plasma cells, and human leukocyte antigen system (HLA)-sharing as well as treatment options such as corticosteroids, intralipids, intravenous immunoglobulins, aspirin and heparin in RPL. Finally, the current state of the art focusing on both diagnostic and therapeutic options was summarized.

Multiple endometrial polyps is associated with higher risk of chronic endometritis in reproductive-aged women

AIM

To determine whether single endometrial polyp (EP) or multiple EP (polyp number ≥ 6) are associated with chronic endometritis (CE).

METHODS

From June 2017 to December 2018, this study enrolled a total of 277 patients, including 92 patients with multiple EP, 82 patients with a single EP and 103 patients without polyps who underwent hysteroscopic examination and polypectomy. Polyps and endometrium samples were obtained and subjected to immunohistochemistry for CD138 to identify plasma cells and CE was diagnosed as CD138-positive plasma cells greater than or equal to 5/high power field. The prevalence of CE was compared and analyzed using the logistic regression model.

RESULTS

All baseline parameters were comparable among the three groups except that the prevalence of abnormal uterine bleeding (AUB) was much higher in both polyp groups than the non-polyp control. The prevalence of CE was significantly higher in the multiple EP group than in the single EP group (58.7% vs 28.0%, P < 0.001). There was no difference on the prevalence of CE between the single EP and the non-polyp groups (28.0% vs 29.1%, P = 0.872). Multivariable analysis revealed that AUB (adjusted OR 2.81, 95% CI 1.35-5.87) and multiple EP (adjusted OR 2.58, 95% CI 1.38-4.82) were independently associated with CE, while the single EP did not increase the odds of CE compared to the non-polyp group (adjusted OR 0.74, 95% CI 0.38-1.45).

CONCLUSION

Multiple EP were positively associated with CE among reproductive-aged women, suggesting a possible hidden etiopathogenetic link between chronic inflammation and multiple EP.

Impact of antibiotic treatment for chronic endometritis on unexplained recurrent pregnancy loss

INTRODUCTION

Recurrent Pregnancy Loss (RPL) affects about 1% of all couples and is likely to cause therapeutic vagrancy and psychological distress. Multiple origins can explain RPL, and recent studies suggest the influence of chronic endometritis. The aim of our study is to evaluate the impact of antibiotic treatment on obstetrical prognosis among patients consulting for RPL with isolated chronic endometritis.

MATERIAL AND METHODS

We conducted a monocentric retrospective comparative study. Patients consulting for RPL, with normal etiologic examinations (except for chronic endometritis), were included. In the case of chronic endometritis, patients could receive antibiotic treatment (14 days of doxycycline and metronidazole). Pregnancy outcomes, collected one year after inclusion, were compared between 3 groups: patients without chronic endometritis, patients with treated chronic endometritis, patients with untreated chronic endometritis. Univariate and multivariate analyses were performed.

RESULTS

42 patients were included. 22 patients had chronic endometritis. Groups were comparable in terms of age, BMI, the number of miscarriages, tobacco consumption, AMH, and FSH levels on day 2. In multivariate analysis, a significant improvement of live birth rate was observed among patients treated for chronic endometritis, compared to the no endometritis group (OR 21.4 [1.93-236.70] p = 0.013) and the untreated endometritis group (OR 24.90 [1.64-376.93] p = 0.020).

CONCLUSION

In our patients examined for RPL, the live birth rate was improved after treatment of chronic endometritis with 14-day antibiotic treatment in comparison to patients with untreated chronic endometritis.

Hysteroscopy and female infertility: a fresh look to a busy corner

Hysteroscopy has evolved from the traditional art of examining the uterine cavity for diagnostic purposes to an invaluable modality to concomitantly diagnose and (see and) treat a multitude of intrauterine pathologies, especially in the field and clinics specialising in female reproduction. This article reviews the literature on the most common cervical, endometrial, uterine and tubal pathologies such as chronic endometritis, endometrial polyps, adenomyosis, endometriosis, endometrial atrophy, adhesions, endometrial hyperplasia, cancer, and uterine malformations. The aim is to determine the efficiency of hysteroscopy compared with other available techniques as a diagnostic and treatment tool and its association with the success of in vitro fertilisation procedures. Although hysteroscopy requires an experienced operator for optimal results and is still an invasive procedure, it has the unique advantage of combining great diagnostic and treatment opportunities before and after ART procedures. In conclusion, hysteroscopy should be recommended as a first-line procedure in all cases with female infertility, and a special effort should be made for its implementation in the development of new high-tech procedures for identification and treatment infertility-associated conditions.

Diagnosis of chronic endometritis: How many CD138+ cells/HPF in endometrial stroma affect pregnancy outcome of infertile women?

PROBLEM

The definition of chronic endometritis (CE) differs among studies, and currently, there is no accepted consensus. This study aimed to establish the minimum number of immunohistochemical analysis of CD138⁺ plasma cells to identify a clinically relevant CE.

METHOD OF STUDY

We performed a retrospective study on 716 infertile patients who never did CE analysis and respective antibiotic treatment before. Samples were obtained by endometrial scratching in the mid-luteal phase before IVF-ET treatment. The number and distribution of CD138⁺ cells were analyzed by immunohistochemistry. Thirty high-power fields (HPF) were evaluated for each sample. Patients were classified in 2 main groups: (a) CD138^low (<5 CD138⁺ cells in all HPFs), (b) CD138^high (≥5 CD138⁺ cells in at least one HPF). Pregnancy outcome was compared among the groups.

RESULTS

In the CD138^high group, β-hCG positive rate, clinical pregnancy rate and live birth rate were significantly decreased (P = .04, P = .01, P = .04, respectively). Also after adjusting for patient age, body mass index (BMI), and clinical characteristics, the β-hCG positive rate (P = .05), clinical pregnancy rate (P = .01) and live birth rate (P = .02) were significantly lower in the CD138^high than those in the CD138^low group. Within the CD138^low group, these parameters were not significantly different between patients without any plasma cells and patients with up to 4 plasma cells/HPF.

CONCLUSION

We conclude that immunohistochemical analysis of CD138⁺ cells is a reliable method to detect CE which can be identified by the presence of ≥5 plasma cells in at least one out of 30 HPF.

Impaired inflammatory state of the endometrium: a multifaceted approach to endometrial inflammation. Current insights and future directions

New insights into the complex and fine-regulated inflammatory mechanisms involved in the endometrium reveal multiple facets to the problem of endometrial inflammation. However, the entity termed chronic endometritis is to date restricted to infectious etiology and managed with antibiotics. Conversely, the concept of impaired inflammatory state of the endometrium (IISE) provides a more global approach to defective endometrial inflammation, considering both infectious and non-infectious etiology. A non-systematic review was done through a search on MEDLINE, EMBASE, Global Health, The Cochrane Library, Health Technology Assessment Database and Web of Science, research registers. Pertinent original and review articles, published in English or French until December 31, 2019, were selected. A compelling body of evidence demonstrates transient, repeated and persistent IISE to be a major factor of most problematic disorders in obstetrics/gynecology, such as endometrial polyps, unexplained infertility, miscarriage, placenta-related pathology and endometrial cancer. When scheduled accordingly, hysteroscopy can play a key role in the IISE assessment. Robust data suggests the pertinence of minimal-effective anti-inflammatory regimens for therapeutic IISE targeting. This review provides a comprehensive update on the multiple facets of inflammation in the endometrial physiology and pathology. Further research is needed to improve classification, diagnosis and treatment of IISE.

Chronic endometritis and reproductive failure: Role of syndecan-1

Chronic endometritis (CE) is an unusual inflammatory condition characterized by endometrial plasmacyte infiltration. It has a high prevalence in women with reproductive failure. Because of its characteristic localization patterns and molecular functions, syndecan-1 has been identified as a biomarker of plasmacyte, and syndecan-1 immunohistochemistry (IHC) becomes the most dependable diagnostic method for CE. In this review, we discuss the association between CE and reproductive failure, the clinicopathological characterization of CE, the function and expression of syndecan-1, the progress of syndecan-1 IHC in the diagnosis of CE, and the prediction of reproductive outcome.

Endometrial CD138 count appears to be a negative prognostic indicator for patients who have experienced previous embryo transfer failure

OBJECTIVE

To explore the predictive value of endometrial CD138 expression in the natural cycle preceding frozen embryo transfer in patients with normal endometrial dating and histopathologic features, who previously failed the transfer of two high-quality fresh embryos.

DESIGN

Retrospective analysis.

SETTING

University-affiliated hospital.

PATIENT(S)

Women with normal endometrial dating and histopathologic features who previously failed the transfer of two high-quality fresh embryos, and who then underwent an endometrial scratching operation preceding a natural cycle.

INTERVENTION(S)

Paraffin-embedded endometrial samples cut into sections for immunohistochemistry staining of CD138 (syndecan-1) expression, then clinical information for these patients reviewed and analyzed.

MAIN OUTCOME MEASURE(S)

Clinical rates of pregnancy and implantation.

RESULT(S)

A total of 141 women met the inclusion criteria. Of these patients, about 31.2% (44 of 141) were positive for CD138 expression, with CD138 counts ranging from 0 to 33. Receiver operating characteristic (ROC) curves were analyzed to determine whether the number of cells expressing CD138 (CD138⁺ cells) predicted a successful pregnancy. The areas under the ROC curves based on CD138⁺ cell density and CD138⁺ cell count were 0.660 and 0.658, respectively. The clinical pregnancy and embryo implantation rates in patients not expressing CD138 (80.04% and 64.9%, respectively) were statistically significantly higher than rates in CD138⁺ patients (52.7% and 46.8%, respectively). In addition, the higher the number of cells expressing CD138, the worse the outcome of the pregnancy. Finally, clinical data showed that free pelvic fluid on the day of endometrial sampling (identified using transvaginal ultrasound) might be a risk factor for CD138 expression.

CONCLUSION(S)

Endometrial CD138⁺ count might be a valuable marker predicting pregnancy outcomes after frozen embryo transfer in patients with normal endometrial dating and histopathologic features who previously failed the transfer of two high-quality fresh embryos.

A New Hysteroscopic Scoring System for Diagnosing Chronic Endometritis

STUDY OBJECTIVE

To develop a new hysteroscopic morphologic scoring system to diagnose chronic endometritis (CE).

DESIGN

Prospective study.

SETTING

Medical hysteroscopy office.

PATIENTS

In total, 320 patients underwent hysteroscopy, dilation and curettage, and endometrial biopsies from February 2017 to June 2018 with the intention of undergoing assisted reproductive technology treatment because of infertility or recurrent miscarriage.

INTERVENTIONS

All patients underwent hysteroscopy, dilation and curettage, and endometrial biopsies for histologic examination and were classified according to the new hysteroscopic morphologic scoring system.

MEASUREMENTS AND MAIN RESULTS

Of the 320 patients, 164 received a diagnosis of CE by histology (group A), whereas 156 patients were found not to have CE (group B). A total of 116 patients were diagnosed by our hysteroscopy scoring system to have CE, and 204 patients did not have CE. The scoring system showed a sensitivity and specificity of 62.8% and 91.7%, respectively. The positive predictive values and negative predictive values were 88.8% and 70.1%, respectively. Receiver operating characteristic analysis showed a cutoff value of >2 and an area under the curve of 0.823. Hysteroscopic and histologic grading showed moderate agreement (κ index = 0.529).

CONCLUSION

Our hysteroscopic scoring system has a high sensitivity and specificity for CE; it is hoped that its use can reduce interobserver variability. Future clinical studies are warranted to confirm the validity and clinical applicability of the proposed hysteroscopic morphologic scoring system for CE.

Dienogest suppresses cellular proliferation status of endometrial polyps and acts differently depending on the morphological type

Administration of Dienogest prior to hysteroscopic polypectomy is empirically performed, but the physiological effects of Dienogest on endometrial polyps are unclear. We aimed to investigate the effects of Dienogest on the proliferation and inflammation of endometrial polyps. We conducted a retrospective case study on 40 menstruating women who underwent hysteroscopic polypectomy at our hospital. We collected clinical data, and the polyps were divided by morphological appearance. The specimens obtained were immunostained for Ki67 as a marker of cellar proliferation and CD138 as a marker of plasmacytes, which are a hallmark of chronic endometritis. Dienogest significantly suppressed the proliferation status of EPs because Dienogest treatment prior to the operation significantly reduced the Ki67 index (41.25 ± 16.85 vs 7.18 ± 9.82, p < 0.01). We found that sessile-type polyps showed a significantly lower Ki67 index than the pedunculated type (12.28 ± 11.12 vs 2.09 ± 2.73, p = 0.026). The presence of CD138-positive cells was more pronounced in sessile-type polyps than in pedunculated polyps (p = 0.018). However, Dienogest treatment showed no apparent effect on inflammation status, as detected by CD138-positive cells. We revealed that Dienogest suppressed cellular proliferation, and morphological classification of endometrial polyps could be used to predict the responsiveness to Dienogest. However, Dienogest might not affect cellular inflammation.

Uterine B Cells Exhibit Regulatory Properties During the Peri-Implantation Stage of Murine Pregnancy

A successful outcome to pregnancy is dependent on the ability of the maternal uterine microenvironment to regulate inflammation processes and establish maternal tolerance. Recently, B cells have been shown to influence pregnancy outcomes as aberrations in their numbers and functions are associated with obstetric complications. In this study, we aimed to comprehensively examine the population frequency and phenotypic profile of B cells over the course of murine pregnancy. Our results demonstrated a significant expansion in B cells within the uterus during the peri-implantation period, accompanied by alterations in B cell phenotype. Functional evaluation of uterine B cells purified from pregnant mice at day 5.5 post-coitus established their regulatory capacity as evidenced by effective suppression of proliferation and activation of syngeneic CD4⁺ T cells. Flow cytometric analysis revealed that the uterine B cell population has an expanded pool of IL-10-producing B cells bearing upregulated expression of co-stimulatory molecules CD80 and CD86 and activation marker CD27. Our investigations herein demonstrate that during the critical stages surrounding implantation, uterine B cells are amplified and phenotypically modified to act in a regulatory manner that potentially contributes toward the establishment of maternal immunological tolerance in early pregnancy.

Successful Natural Pregnancy Using Whole Systems Traditional Chinese Medicine in a Complex Anovulatory Patient After Multiple Unsuccessful In Vitro Fertilization Treatments: A Case Report

Background: Women who have anovulatory infertility due to polycystic ovary syndrome (PCOS) rely primarily on medical fertility treatment to conceive. If this treatment fails, the odds of success of conceiving naturally are extremely small, limited by the lack of ovulation and its unpredictability. Whole systems Traditional Chinese Medicine (WS-TCM), which includes acupuncture, Chinese herbs, nutrition and supplements, and lifestyle recommendations, has traditionally been used to prepare the body for pregnancy and to induce ovulation in PCOS patients with anovulatory infertility. Case: This case describes the treatment of a complex anovulatory PCOS patient using a WS-TCM approach to induce ovulation and produce a natural uncomplicated pregnancy after multiple rounds of in vitro fertilization with and without preimplantation genetic screening and also with and without acupuncture were unsuccessful. Results: After 9 unsuccessful frozen embryo transfers, 3 of which with genetically tested euploid embryos, this previously anovulatory patient was able to ovulate, conceive, and carry a healthy pregnancy to term. Conclusions: This case suggests that in challenging cases of infertility in the setting of PCOS, the multifaceted approach of WS-TCM may provide an alternative means to induce ovulation and increase the odds of conceiving.

Review: Chronic endometritis and its effect on reproduction

AIM

Chronic endometritis (CE) is a disease of continuous and subtle inflammation characterized by the infiltration of plasma cells in the endometrial stromal area. Although the clinical significance of CE has been thought in clinical practice for a long time because it is either asymptomatic or presents with subtle symptoms, recent studies have shown the potential adverse effects of CE on fertility. In the present review, we focus on the concept, diagnosis, etiology, pathophysiology, diagnosis, impact on reproduction and treatment for it to understand CE.

METHODS

The published articles were reviewed.

RESULTS

The prevalence of CE has been found to be 2.8-56.8% in infertile women, 14-67.5% in women with recurrent implantation failure (RIF), and 9.3-67.6% in women with recurrent pregnancy loss. Microorganisms are thought to be a main cause of CE, since antibiotic treatment has been reported to be an effective therapy for CE. Common bacteria are frequently detected in the uterine cavity of CE patients by microbial culture. In CE endometrium, the prevalence of immune cells and decidualization has been reported to be modified, and these modifications are thought to adversely affect fertility. The gold standard for the diagnosis of CE is the histological detection of plasma cells in the stromal area of the endometrium in endometrial specimens, although universally accepted criteria for the diagnosis of CE have not been determined. The treatment currently thought to be most effective for the recovery of fertility in CE is administration of oral antibiotics. Patients whose CE has been cured have been reported to have a higher ongoing pregnancy rate, clinical pregnancy rate, and implantation rate compared with patients with persistent CE.

CONCLUSION

CE greatly affects implantation and impairs fertility. Antibiotic administration is an effective therapeutic option. Pregnancy rate in in vitro fertilization is improved when CE is cured by antibiotic.

Endometritis: new time, new concepts

Endometritis is subdivided into two categories. Acute endometritis is symptomatic and characterized by microabscess formation and neutrophil invasion in the endometrial superficial epithelium, gland lumina, and uterine cavity. Chronic endometritis is rather silent and recognized as unusual plasmacyte infiltration in the endometrial stromal areas. Over the last decade, studies have disclosed the potential association between poor reproductive outcomes and endometritis, particularly chronic endometritis. The aim of this review is to address the current literature surrounding chronic endometritis and highlight recent advances in the research of this long-neglected gynecologic disease.