Impact of oral antibiotic treatment for chronic endometritis on pregnancy outcomes in the following frozen-thawed embryo transfer cycles of infertile women: a cohort study of 640 embryo transfer cycles

Factors influencing endometrial receptivity in women with recurrent implantation failure

BACKGROUND

Embryo implantation involves two key elements: a good quality embryo and receptive endometrium. Endometrial receptivity abnormalities are known as one of the possible causes of recurrent implantation failure (RIF), especially when the embryo is euploid. This study was aimed to evaluate the impact of age and other clinical factors on endometrial receptivity in women with RIF.

METHODS

68 women with RIF (defined as at least three unsuccessful transfers of good quality embryo of at least 1BB category of blastocysts) and 49 controls (women undergoing IVF treatment because of idiopathic infertility or male factor) were included to the study. After preparation of the endometrium by the hormone replacement therapy endometrial biopsies were taken from each patient and sequenced with beREADY test TAC targeting 67 biomarker genes for endometrial receptivity. Depending on the test result patients were classified into one of four different groups: pre-receptive (n = 16), early-receptive (n = 54), receptive (n = 44) and late-receptive (n = 3).

RESULTS

In women with RIF pre-receptive endometrium has been detected substantially more often than in controls - 13 (19,1%) vs. 3 (6,1%) patients (p = 0,043). Early-receptive endometrium was diagnosed in the majority of patients with idiopathic infertility - 12 (66.7%) vs. 6 (33.3%) women (p = 0.042) and with polycystic ovary syndrome (PCOS) - 12 (70,6%) vs. 3 (17.7%) women (p = 0,0447). We found significant association between abnormal endometrial receptivity and patient's age and duration of infertility. Young women were diagnosed significantly more often as normal or late-receptive, whereas older women with longer history of infertility as early-receptive and pre-receptive.

CONCLUSIONS

In patients with RIF in comparison to other women undergoing IVF procedures, patient's age and infertility duration are the most important factors related to endometrial receptivity abnormalities, indicating that older women with a longer history of infertility may benefit the most from endometrial receptivity testing.

TRIAL REGISTRATION

Not applicable.

If CE affects infertile women's outcomes after surgery?

OBJECTIVE

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

MATERIALS AND METHODS

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

OUTCOME

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

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.

Risk factors of chronic endometritis in women who have undergone hysteroscopy: a prospective nested case-control study

There is limited research on risk factors for chronic endometritis regarding reproductive history and clinical symptoms. Thus, this nested case-control study identified risk factors for chronic endometritis in women who have undergone hysteroscopy. Endometrial tissue sections were obtained from 502 women with intrauterine disorders who underwent hysteroscopy. Chronic endometritis was diagnosed via CD138 immunostaining. The women were divided into two groups: 271 women without chronic endometritis and 231 women with chronic endometritis. The prevalence of chronic endometritis was 46%. Univariate logistic regression revealed that prolonged menstruation and intermenstrual bleeding were associated with chronic endometritis, and subsequent multivariate logistic regression analyses showed that these were further independently associated. With univariable logistic regression, the gravidity and abortion history were correlated with chronic endometritis; however, no significant correlation was found with the adjusted odds ratio (OR) of 0.74 (95% confidence interval [CI] 0.46-1.19) or 0.76 (95% CI 0.58-1.11), respectively. No significant correlation was found between caesarean section history and the rates of chronic endometritis. No significant difference was found in all other variables between the three groups with > 5, ≤ 5 plasma cells and in a unknown group. Prolonged menstruation and intermenstrual bleeding were risk factors associated with chronic endometritis. Chronic endometritis should be considered and CD138 immunohistochemical examination should be recommended in women with these symptoms.

Prevalence and risk factors for chronic endometritis in patients with adenomyosis and infertility: a retrospective cohort study

BACKGROUND

To explore the incidence of chronic endometritis (CE) in patients with infertility and different forms of adenomyosis and analyze potential high-risk factors for infection.

METHODS

This retrospective cohort study included 154 patients with infertility in the Liuzhou Maternity and Child Healthcare Hospital. Among them, 77 patients with adenomyosis were divided into four subgroups based on magnetic resonance imaging (MRI): internal, exterior, intramural, and full-thickness. Meanwhile, 77 patients did not have adenomyosis. Hysteroscopy and endometrial biopsy were performed in the proliferative phase. The main outcome measures were the morphology of the endometrium, syndecan-1 (CD138) immunohistochemical staining, clinical characteristics, and prevalence of CE in the adenomyosis subgroups.

RESULTS

In comparison to the non-adenomyosis group, the adenomyosis group had significantly higher body mass index (BMI) and CA125 levels. The menstrual cycle in the adenomyosis group was significantly shorter, and menarche was significantly earlier. In comparison to the non-adenomyosis group, the adenomyosis group had a significantly higher diagnostic rate of CE (75.3% vs. 46.8% according to hysteroscopy and 74.0% vs. 33.8% according to histopathology, both with p < .050). The incidence of CE was significantly lower in patients with internal adenomyosis when compared with the other three subgroups. Increased BMI contributed to a higher risk of CE.

CONCLUSIONS

The prevalence of CE was significantly higher in patients with adenomyosis and infertility. The differences in the incidence of CE are closely associated with the classification of adenomyosis. When patients with infertility are diagnosed with adenomyosis, it is recommended to identify the subtype and screen for endometritis.

Endometrial preparation protocols did not impact pregnancy outcomes of patients with cured chronic endometritis

RESEARCH QUESTION

Do endometrial preparation protocols have an effect on pregnancy outcomes in patients with cured chronic endometritis?

DESIGN

A retrospective study was conducted on 3721 infertile patients from December 2018 to August 2020. Endometrial tissues obtained during the proliferative phase were immunostained for CD138. The presence of CD138-positive cells within the stromal cells indicated chronic endometritis. All patients diagnosed with chronic endometritis received oral antibiotics. Patients underwent endometrial preparation and frozen embryo transfer once chronic endometritis was cured. This study compared various endometrial preparation protocols to assess their effects on pregnancy outcomes. Additionally, it aimed to investigate differences in pregnancy outcomes between patients without chronic endometritis and patients with cured chronic endometritis while following the same endometrial preparation protocol.

RESULTS

Almost no differences in pregnancy outcomes were observed between natural cycle, hormone replacement therapy (HRT) and gonadotrophin-releasing hormone agonist-HRT (GnRH agonist-HRT) protocols in patients without chronic endometritis and patients with cured chronic endometritis. The only notable difference was that, among women without chronic endometritis, the early miscarriage rate was higher for the GnRH agonist-HRT protocol (25.8%) compared with the natural cycle (17.4%) and HRT (17.7%) protocols (P = 0.025). However, this difference was not significant after adjusting for confounders (adjusted OR 1.383, 95% CI 0.931-2.055). The live birth rate, clinical pregnancy rate, early miscarriage rate, ectopic pregnancy rate and ongoing pregnancy rate did not differ significantly (P > 0.05) between patients without chronic endometritis and patients with cured chronic endometritis who underwent natural cycle, HRT and GnRH agonist-HRT protocols.

CONCLUSION

Endometrial preparation protocols had no impact on pregnancy outcomes in patients with cured chronic endometritis.

Modified Hongteng Baijiang decoction enema improves sequelae of pelvic inflammatory disease by regulating the LIF/JAK2/STAT3 pathway and gut microbiota

OBJECTIVE

The sequelae of pelvic inflammatory disease (SPID) are major causes of secondary infertility. Modified Hongteng Baijiang decoction (MHTBD) has produced positive results in the treatment of patients with chronic pelvic inflammatory disease; however, its role in SPID remains elusive. Therefore, this study clarified the role of MHTBD in SPID pathogenesis.

METHODS

The main components in MHTBD were analyzed by using liquid chromatography‒mass spectrometry (LC/MS). An SPID rat model was established, and the rats were treated with different doses of MHTBD (0.504 g of raw drug/kg, 1.008 g of raw drug/kg, and 2.016 g of raw drug/kg). Endometrial pinopodes were observed via scanning electron microscopy, endometrial thickness and inflammatory cell infiltration were assessed via HE staining, and the expression of estrogen receptor (ER), progesterone receptor (PR), integrin β3 (ITGB3), and CD31 in the endometrium was detected by using immunohistochemistry. Western blot analysis was used to detect the protein expression of LIF, JAK2, p-JAK2, STAT3, and p-STAT3 in the endometrium. Moreover, the changes in the gut microbiota were analyzed via 16S rRNA sequencing.

RESULTS

MHTBD improved endometrial receptivity, attenuated endometrial pathologic damage, reduced inflammatory cell infiltration, decreased ER and PR expression in the endometrium, and promoted the expression of LIF, p-JAK2, and p-STAT3 in the endometrium (p < .05) in SPID rats. Additionally, MHTBD treatment affected the composition of the gut microbiota in SPID rats. Furthermore, MHTBD attenuated endometrial receptivity and pathological damage in SPID rats by promoting the LIF/JAK2/STAT3 pathway.

CONCLUSION

MHTBD attenuates SPID in rats by promoting the LIF/JAK2/STAT3 pathway and improving the composition of the gut microbiota. MHTBD may be a valuable drug for SPID therapy.

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.

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

RESEARCH QUESTION

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

DESIGN

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

RESULTS

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

CONCLUSIONS

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

Liriodendrin exerts protective effects against chronic endometritis in rats by modulating gut microbiota composition and the arginine/nitric oxide metabolic pathway

BACKGROUND

Chronic endometritis (CE), a gynecological disease, is characterized by inflammation. Liriodendrin is reported to exhibit anti-inflammatory properties. However, the therapeutic effects of liriodendrin on CE and the underlying molecular mechanisms have not been elucidated. This study aimed to investigate the therapeutic effects of liriodendrin on CE in rats and the underlying mechanisms.

METHODS

A CE rat model was established and administered with liriodendrin for 21 days. The serum levels of inflammatory cytokines were examined using enzyme-linked immunosorbent assay. The uterine mRNA levels of cytokines were examined using quantitative real-time polymerase chain reaction analysis. The activation of the Toll-like receptor 4 (TLR4)/NF-κB pathway was investigated using western blotting analysis. The effects of liriodendrin on intestinal flora and serum metabolites were examined using 16S rRNA sequencing and untargeted serum metabolomics, respectively. The protein and mRNA levels of arginase-2 (Arg-2) and the nitric oxide (NO) metabolic pathway-related factors were assessed. Molecular docking was performed to explore the interaction between liriodendrin and Arg-2.

RESULTS

Liriodendrin alleviated the CE-induced pathological changes in the uterus, modulated the serum levels of inflammatory cytokines, and downregulated the mRNA and protein levels of TLR4/NF-κB pathway-related factors. Treatment with liriodendrin mitigated the CE-induced upregulation of Firmicutes/Bacteroidetes ratio and Lachnospiraceae abundance and downregulation of Ruminococcaceae abundance. Serum metabolomic analysis revealed that liriodendrin regulated the biosynthesis of choline metabolism pathway-related factors. Liriodendrin suppressed the CE-induced upregulation of Arg-2 and downregulation of inducible nitric oxide synthase (iNOS) expression, and NO levels by directly binding to the amino acid residues of Arg-2 through hydroxyl bonds.

CONCLUSIONS

Liriodendrin exerted therapeutic effects on CE in rats through the alleviation of inflammation by modulating the gut microbiota structure, directly downregulating Arg-2, and regulating the arginine/NO metabolic pathway.

A Method to Study the Meiotic Recombination Map in Human Preimplantation Blastocysts

Homologous recombination plays pivotal roles in physical attachments and genetic diversity. In the past, it was studied among individuals from different populations. However, only few gametes from individual could generate offspring, which limits its exploration in nature selection. In the last few years, preimplantation blastocysts based on trio SNP-chip data were available in individuals for preimplantation genetic testing (PGT). In this protocol, we demonstrate how to detect meiotic recombination events and construct the genetic map based on trio SNP-chip data, obtained from biopsied blastocysts and their related individuals in PGT cycles, which may allow better understanding of recombination events in nature selection.

Comparison of clinical effectiveness and subsequent fertility between hysteroscopic resection and vaginal repair in patients with cesarean scar defect: a prospective observational study

OBJECTIVE

To evaluate the clinical effectiveness and pregnancy rate after hysteroscopic resection (HR) and/or vaginal repair (VR) in patients with cesarean scar defect (CSD).

METHODS

This prospective observational study enrolled 191 patients who received CSD surgery in the First affiliated hospital of Sun Yat-sen University between September 2019 to February 2022 (96 in HR and 95 in VR, respectively). Patient follow-up were performed three months after surgery in both groups by transvaginal ultrasound to confirm the presence of fluid in the niche, along with the resolution of prolonged menses at the same time. The primary outcome was the clinical effectiveness between HR and VR, identified by the resolution of prolonged menses.

RESULTS

The rates of niche-fluid disappearance (70.1% vs 60.2%, P = 0.176) and prolonged menses resolution (74.8% vs 80.0%, P = 0.341) were comparable for HR and VR. A subgroup analysis for niche size revealed that HR provides patients with small niche a more favorable rate of menstrual resolution compared to VR (size of niche ≤ 15 mm2, aOR = 3.423, 95% confidence interval [CI] 1.073-10.918), but patients with large niche experience a lower rate of resolution compared to VR (size of niche > 25 mm2, aOR = 0.286, 95% CI 0.087- 0.938). During follow-up, 41 patients who wanted to conceive became pregnant. Kaplan-Meier estimates of the cumulative probability of pregnancy at 12 months and 24 months were 47.1% (95% CI: 34.5%, 58.8%) and 63.8% (95% CI: 52.5%, 72.9%), respectively. The median pregnancy time was 22 months (95% CI: 14.2, 29.8) after VR and 12 months (95% CI: 8.3, 15.7, Gehan-Breslow-Wilcoxon P = 0.021) after HR. Among patients with subsequent infertility, 31.6% achieved pregnancy by unassisted mode and 29.8% by IVF/ICSI. Moreover, among patients with previously failed IVF/ICSI treatment, 60% (12/20) obtained pregnancy, including 71.4% (10/14) after HR and 33.3% (2/6) after VR.

CONCLUSIONS

Hysteroscopic resection is as effective as vaginal repair at relieving symptoms of CSD-associated prolonged menses. Hysteroscopic resection is the modality of choice with an improvement in prolonged menses for small niche, while vaginal might be considered for a large niche. Furthermore, surgical intervention could improve the clinical pregnancy rate of CSD patients. All of these provide evidence for the individualized management of CSD.

Increasing expression of STING by ERα antagonizes LCN2 downregulation during chronic endometritis

Chronic endometritis has a high incidence in infertile women, which is caused by endometrial microbiome infection. In response to microbial infection, the role of defensins during chronic endometritis need explored. Besides, the expression of estrogen and its receptors vary in different menstrual cycles, but their roles in chronic endometritis are still unclear. In this study, we used the human endometrial tissues to examine the expression of antimicrobial peptides (AMPs) α-defensin hNP-1 and β-defensins hBD-1, hBD-2, hBD-3, hBD-4 and LCN2. We found the expression of hBD-1 and LCN2 were downregulated in endometritis tissues, while the expressions of hBD-2, hBD-3, hBD-4, hNP-1, and estrogen and ERα were upregulated in chronic endometritis tissues compared to normal tissues. The expression and phosphorylation of STING, which is a crucial mediator of mammalian innate immunity in response to pathogens, was regulated with the treatment of ERα inhibitor raloxifene (Rx). Furthermore, using with the estrogen receptor inhibitor Rx and STING inhibitor H-151 significantly decreases the LCN2 expression. Taken together, these results suggested ERα was upregulated to modulate STING expression inducing LCN2 antimicrobial peptide expression to modulate the mucosal immunity during chronic endometritis.

Storage time does not influence pregnancy and neonatal outcomes for first single vitrified high-quality blastocyst transfer cycle

RESEARCH QUESTION

Does blastocyst storage time have an impact on pregnancy and neonatal outcomes following the first single vitrified/warmed high-quality blastocyst transfer cycle for young women?

DESIGN

Retrospective cohort study in a university-affiliated reproductive medical centre.

RESULTS

A total of 2938 patients undergoing their first frozen embryo transfer (FET) cycle with a single high-quality blastocyst (Day 5: 3BB and above; Day 6: 4BB and above) transferred were divided into five groups: Group A with storage time ≤3 months (n = 1621), Group B with storage time of 4-6 months (n = 657), Group C with storage time of 7-12 months (n = 225), Group D with storage time of 13-24 months (n = 104), and Group E with storage time of 25-98 months (n = 331). After adjusting for confounding factors by multivariate logistic regression, there were no significant differences in live birth rate [Group A as reference; Group B: adjusted odds ratio (aOR) 0.954 (95% CI 0.791- 1.151); Group C: aOR 0.905 (95% CI 0.674-1.214); Group D: aOR 0.727 (95% CI 0.474-1.114); Group E: aOR 1.185 (955 CI 0.873-1.608)], β-human-chorionic-gonadotropin-positive rate, clinical pregnancy rate and miscarriage rate between Group A and the other groups. Among all singletons born after FET, there were no significant differences with regards to gestational age, preterm birth, birthweight, low birthweight, high birthweight and macrosomia.

CONCLUSION

Long-term cryostorage of human vitrified high-quality blastocysts does not affect pregnancy or neonatal outcomes.

HMGB1 induces macrophage pyroptosis in chronic endometritis

BACKGROUND

Chronic endometritis (CE) reflects the local imbalance in the endometrial immune microenvironment after inflammation. High mobility group box 1 (HMGB1) is highly involved in both immunity and inflammation. In this study, we aimed to explore the roles of HMGB1 in the endometrium of patients with CE.

METHODS

Endometrium and uterine fluid HMGB1 were tested in a cohort of infertile patients with or without CE. Expression levels of the pyroptosis marker, gasdermin D (GSDMD)-N-terminal (NT), in the human endometrium of patients with CE and controls were determined. Next, the role of HMGB1 as a driver of macrophage pyroptosis was investigated using human THP-1 cells in vitro and a CE mouse model in vivo.

RESULTS

High expression levels of HMGB1 in biopsied endometrial tissue and uterine fluid were confirmed in a cohort of patients with CE. Positive correlation between the number of CD138+ cells and HMGB1 mRNA expression level were detected (rs = 0.592, P < 0.001). Meanwhile, we found that GSDMD-NT expression was significantly increased in the CE endometrium at both the transcriptional and translational levels. Moreover, co-localization of GSDMD-NT and macrophages was confirmed via the double immunostaining of GSDMD-NT and CD68. In vitro experiments revealed that macrophage pyroptosis was induced by HMGB1 in human THP-1-derived macrophages. Treatment with glycyrrhizic acid, an inhibitor of HMGB1, significantly suppressed endometrial pyroptosis and inflammation in the CE mouse model.

CONCLUSIONS

HMGB1 effectively induced macrophage pyroptosis in the human endometrium, suggesting that its inhibition may serve as a novel treatment option for CE.

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.

Benefits of antibiotics and the optimal time interval between biopsy and the next embryo transfer in patients with chronic endometritis

This study evaluated the effects of antibiotics on the implantation rate (IR) as well as the optimal time interval from endometrial biopsy to subsequent embryo transfer (ET) to explore proper chronic endometritis (CE) management. We retrospectively analyzed the clinical data of patients who had failed 1 or 2 ET cycles and underwent hysteroscopy. CE was diagnosed when 3 or more cluster of differentiation138 - positive plasma cells were found per high-power field. We divided the patients into 3 groups: those with CE who received antibiotics (group 1), those with CE who did not receive antibiotics (group 2), and those without CE (group 3). We found that IR was significantly higher in Group 1 than in Group 2. Furthermore, while the IR in Groups 1 and 3 was significantly higher when the time interval was < 6 months than when the time interval was > 6 months, there were no significant differences in the IR when the time interval was < 2 months or ≥ 2 months but < 6 months. Postbiopsy oral antibiotic therapy significantly improved IR in patients with CE, whereas increasing the time interval from biopsy to ET reduced IR. This study may help to find a higher potential for success in the medical management of patients with CE.

Impact of antibiotic cured chronic endometritis on perinatal outcomes: Re-evaluation of a cohort study with a detailed follow-up

PROBLEM

The impact of antibiotic-cured chronic endometritis (CE) on perinatal outcomes of patients conceived with frozen embryo transfer (FET) was unclear.

METHOD

This study was to re-evaluate the perinatal outcomes of a cohort of infertile patients who had undergone endometrial biopsy for CE detection from February 2018 to December 2019 and successfully delivered babies after FET. The study population was divided into two groups: the non-CE (NCE) group (0-4/HPF CD138) and the cured-CE (CCE) group (CD138+/HPF≥5 and has been cured after one or two rounds of antibiotic treatment). For subgroup analysis, the NCE group was further divided into subgroup 1 (CD138+/HPF = 0), subgroup 2 (CD138+/HPF = 1-4 with antibiotic treatment), and subgroup 3 (CD138+/HPF = 1-4 without antibiotic treatment) RESULTS: A total of 321 live births, including 210 in the NCE group and 111 in the CCE group were analyzed. The prevalence rates of premature rupture of the membrane and preterm birth were comparable between NCE and CCE (6.2% vs. 7.1% and 10.8% vs. 10.1%, respectively) groups. In addition, no differences were detected in the rates of placenta-mediated complications, such as preeclampsia, placenta abruption, or low birthweight. Multiple logistic analyses confirmed that CCE was not associated with an increased risk of any adverse perinatal outcomes. Subgroup analysis in NCE failed to find any significant differences in the incidences of obstetrical and neonatal complications.

CONCLUSIONS

CCE might not increase the risks of adverse perinatal outcomes after antibiotic treatment.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

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

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

Effect of different antibiotic therapies on the reproductive outcomes of fresh embryo transfer for chronic endometritis: A retrospective cohort study

OBJECTIVE

To investigate the reproductive outcomes by comparing two kinds of antibiotic schemes for chronic endometritis (CE) in infertile women's fresh embryo transfer (FET) cycles and identify subgroups of patients with CE who need long-term antibiotics treatment.

DESIGN

A retrospective cohort study.

SETTING

University-based reproductive medical center.

PATIENT(S)

A total of 492 women with CD138-positive plasmacytes per 10 high-power fields (CD138+/10HPF).

INTERVENTION(S)

Hysteroscopy was performed and endometrial biopsy samples were collected in the proliferative phase. Long-term or short-term antibiotics were administrated. After antibiotics treatment, patients underwent in vitro fertilization (IVF)/ intracytoplasmic sperm injection (ICSI) and received ET.

MAIN OUTCOME MEASURE(S)

Ongoing pregnancy rate, clinical pregnancy rate, clinical miscarriage rate.

RESULT (S)

There were no significant differences in pregnancy outcomes between patients with CD138+/10HPF 1-4 (low-grade CE) who received long-term antibiotic therapy and short-term antibiotics groups. Among women with CD138+/10HPF ≥5 (high-grade CE), live birth rate (48.4% vs. 14.7%, p = .001), clinical pregnancy rate (66.7% vs. 35.3%, p = .002) and ongoing pregnancy rate (59.1% vs. 20.6%, p < .001) in the long-term arm were significantly higher than that in the short-term arm. The clinical miscarriage rate (21.0% vs. 58.3%, p = .013) was statistically lower in the long-term antibiotics group, but no statistical differences were found between the two groups in preterm delivery rate.

CONCLUSION

Long-term antibiotics treatment was a sensible choice to improve pregnancy outcomes in women with CD138+/10HPF ≥5 (high-grade CE). The pregnancy outcomes of women with low-grade CE only defined by histological diagnosis were not greatly improved after antibiotic therapy. Therefore, we recommended the proper diagnosis criteria were CD138+/10HPF ≥5 pathologically.

Therapeutic efficacy of gentle endometrial curettage on antibiotic-resistant chronic endometritis in infertile women

Purpose

To identify the efficacy of endometrial curettage on antibiotic-resistant chronic endometritis (CE) in infertile women.

Methods

Of 1580 women with CE, 87 with antibiotic-resistant CE after two to five cycles of antibiotic treatment were recruited between 2019 and 2021. The women who underwent endometrial curettage without applying any force and, in the subsequent menstrual cycle, endometrial sampling for CD138 immunostaining without antibiotic use. Pregnancy outcomes after in vitro fertilization treatment were analyzed in women who did not desire endometrial curettage and in those with cured and persistent CE after endometrial curettage.

Results

In 64 women who underwent endometrial curettage, the number of CD138-positive cells decreased from 28.0 ± 35.3 to 7.7 ± 14.0 (p < 0.0001), and CE in 41 women (64.1%) was cured (<5 CD138-positive cells). The pathological findings detected 3.1% of endometrial hyperplasia and 1.6% of endometrial cancer. The ongoing pregnancy rates in women aged ≤42 without endometrial curettage were significantly lower than those of women with cured and persistent CE (26.7%, 67.6%, and 57.1%, respectively, p = 0.03).

Conclusions

Gentle endometrial curettage for antibiotic-resistant CE significantly decreased the number of CD138-positive cells, resulting in improved pregnancy outcomes regardless of remaining CE. Endometrial curettage is also important as a screening for endometrial malignancy.

New biopsy after antibiotic treatment: effect on outcomes of assisted reproduction in patients with infertility and chronic endometritis

RESEARCH QUESTION

What is the effect of chronic endometritis on patients with infertility, the necessity of endometrial re-examination and the effect of improving chronic endometritis after one cycle of antibiotic treatment on pregnancy outcomes?

DESIGN

Infertile patients (n = 4003) who underwent IVF and intracytoplasmic sperm injection treatment were included. Pregnancy outcomes of groups positive for chronic endometritis were compared with groups that were negative (group 1). Patients that were positive were divided into the chronic endometritis new biopsy group (group 2) and chronic endometritis non-re-examination group (group 3). After doxycycline treatment and re-examination, the chronic endometritis new biopsy group was divided into improved chronic endometritis group (ICE) and not-improved chronic endometritis group (NICE), and their general indicators and reproductive outcomes were compared.

RESULTS

No significant difference was observed in embryo implantation, early or late pregnancy loss, ectopic pregnancy, clinical pregnancy and live birth rates between groups 2 and 3. The clinical pregnancy and live birth rates in the NICE group were significantly lower than those in the ICE group (P = 0.008 and P = 0.001, respectively). After controlling for potential confounding factors, age, average number of high-quality embryos, endometrial thickness on the day of embryo transfer and number and type of embryo transfer were factors associated with live birth rates.

CONCLUSIONS

Endometrial re-examination of women with chronic endometritis treated with doxycycline had no effect on pregnancy outcomes. The first cycle of doxycycline treatment could effectively improve reproductive outcomes of women with five or more CD138+ cells/high-power field.

Challenges in Clinical Diagnosis and Management of Chronic Endometritis

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

Impact of antibiotic treatment for chronic endometritis on pregnancy outcomes in women with reproductive failures (RIF and RPL): A systematic review and meta-analysis

Objective

The aim of this study was to investigate the effect of antibiotic treatment for chronic endometritis (CE) on reproductive outcomes.

Design

Systematic review and meta-analysis.

Patients

Women with reproductive failures, including recurrent implantation failure (RIF), and recurrent pregnancy loss (RPL).

Interventions

Literature searches were performed using three electronic databases (PubMed, Embase, and Web of Science) until 1 December 2021 (without date restriction). The following comparators were included: women with CE receiving antibiotics vs. untreated controls; women with cured CE vs. women with normal endometrial histology (negative for CE); and women with cured CE vs. women with persistent CE (PCE). The summary measures were indicated as odds ratio (OR) with a 95% confidence interval (CI).

Main outcome measures

These include on-going pregnancy rate/live birth rate (OPR/LBR), clinical pregnancy rate (CPR), and miscarriage rate/pregnancy loss rate (MR/PLR).

Results

A total of 2,154 women (from twelve studies) were enrolled. Compared with the control group, women with CE receiving antibiotics did not show a statistically significant difference in OPR/LBR (P = 0.09) and CPR (P = 0.36), although there was a lower MR (P = 0.03). Women with cured CE have higher OPR/LBR (OR 1.57) and CPR (OR 1.56) in comparison with those with non-CE. There was a statistically significantly higher OPR/LBR (OR 6.82, P < 0.00001) and CPR (OR 9.75, P < 0.00001) in women with cured CE vs. those with persistent CE.

Conclusion

While antibiotic treatment is a sensible option to cure CE, more well-designed prospective studies are needed to evaluate the reproductive impact of antibiotic treatment. Cured CE provides high-quality maternal conditions for subsequent embryo transfer and successful pregnancy.

Chronic Endometritis in Infertile Women: Impact of Untreated Disease, Plasma Cell Count and Antibiotic Therapy on IVF Outcome-A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aims to evaluate the impact of chronic endometritis (CE) and its therapy on in vitro fertilization (IVF) outcome. Additionally, we aim to investigate whether various degrees of CE severity may exert a different effect on IVF outcome. Ongoing-pregnancy rate/live-birth-rate (OPR/LBR), clinical-pregnancy rate (CPR), and miscarriage rate (MR) were calculated. A total number of 4145 patients (from ten studies) were included. Women with CE had lower OPR/LBR (OR 1.97, p = 0.02) and CPR (OR 2.28, p = 0.002) compared to those without CE. CE cure increased OPR/LBR (OR 5.33, p < 0.0001) and CPR (OR 3.64, p = 0.0001). IVF outcome was comparable between women with cured CE and those without CE (OPR/LBR, CPR and MR: p = ns). Women with severe CE had lower OPR/LBR (OR 0.43, p = 0.003) and CPR (OR 0.40, p = 0.0007) compared to those mild CE. Mild CE showed no influence on the IVF outcome as compared to women without CE (OPR/LBR, CPR and MR: p = ns). Based on this data analysis, CE significantly reduces OPR/LBR and CPR in women undergoing IVF. Importantly, CE resolution after antibiotic therapy may improves IVF outcome, leading to similar OPR/LBR and CPR as compared to unaffected patients. The negative effects of CE on IVF outcome may be restricted to severe disease, whereas mild CE may have no influence on IVF success.

Vaginom- und „Endometriom“-Diagnostik bei Kinderwunsch

Die molekulare Diagnostik der Vaginal- und Endometriumflora ermöglicht neue Einblicke in die physiologische Besiedlung des weiblichen Genitaltrakts. Wesentlich ist hierbei eine Dominanz von bestimmten Laktobazillenarten bei gleichzeitig geringer Artenvielfalt. Die Bildung von D‑Laktat ist eine entscheidende Voraussetzung für die Abwehr von sexuell übertragbaren Erkrankungen, den Erfolg einer In-vitro-Fertilisation sowie einen ungestörten Schwangerschaftsverlauf. Eine Störung der Flora durch pathogene Bakterienarten mit der Folge des Auftretens einer bakteriellen Vaginose oder einer chronischen Endometritis kann zu Implantationsversagen, Aborten und Frühgeburtsbestrebungen führen. Bei wiederholtem Implantationsversagen ermöglicht eine Mikrobiomdiagnostik – im Gegensatz zur klassischen Kultur, den Amsel-Kriterien oder dem Nugent-Score – einen sehr viel detaillierteren Einblick in die Pathophysiologie, da sich entscheidende Bakterienarten nur schwer oder gar nicht anzüchten lassen. Dies erlaubt eine sehr viel bessere Planung der Therapie zur Wiederherstellung physiologischer Verhältnisse.

Prevalence of and risk factors for chronic endometritis in patients with intrauterine disorders after hysteroscopic surgery

OBJECTIVE

To identify the prevalence of and risk factors for chronic endometritis (CE) in patients with intrauterine disorders and the therapeutic efficacy of hysteroscopic surgery in the treatment of CE without antibiotic therapy.

DESIGN

Prospective cohort study.

SETTING

Hospital specializing in reproductive medicine.

PATIENT(S)

The study population consisted of 350 women with infertility, of whom 337 were recruited, who underwent hysteroscopic surgery between November 2018 and June 2021. Eighty-nine consecutive patients without intrauterine disorders were also recruited as controls.

INTERVENTION(S)

Endometrial samples were collected during the surgery for CD138 immunostaining for the diagnosis of CE. In women diagnosed with CE, endometrial biopsy was performed without antibiotic use in the subsequent menstrual cycle.

MAIN OUTCOME MEASURE(S)

Prevalence of and risk factors for CE in intrauterine disorders and therapeutic effects of hysteroscopic surgery on CE.

RESULT(S)

The prevalence of CE with ≥5 CD138-positive cells in women with no intrauterine disorder and with endometrial polyps, myomas, intrauterine adhesions (IUAs), and septate uterus was 15.7%, 85.7%, 69.0%, 78.9%, and 46.2%, respectively. A multivariate analysis revealed that CE was diagnosed significantly more often in the endometrial polyp (odds ratio, 27.69; 95% confidence interval, 15.01-51.08) and IUA groups (odds ratio, 8.85; 95% confidence interval, 3.26-24.05). The rate of recovery from CE with surgery in women with endometrial polyps, myomas, IUA, and septate uterus was 89.7%, 100%, 92.8%, and 83.3%, respectively.

CONCLUSION(S)

Endometrial polyp and IUA were risk factors for CE. Most CE cases with intrauterine disorders were cured with hysteroscopic surgery without antibiotic therapy, regardless of the type of intrauterine abnormalities.

Lincomycin Administration against Persistent Multi-Drug Resistant Chronic Endometritis in Infertile Women with a History of Repeated Implantation Failure

Chronic endometritis (CE) is an infectious disease of the uterine lining, which is characterized by endometrial stromal plasmacyte (ESPC) infiltration. CE is often seen in infertile women with a history of repeated implantation failure (RIF) following an in vitro fertilization-embryo transfer program, recurrent pregnancy loss, and unknown etiology. Oral antibiotic agents, such as doxycycline, metronidazole, ciprofloxacin, azithromycin, and moxifloxacin, have been prescribed and are effective in the treatment of CE. Multi-drug resistance (MDR), however, is an emerging issue, as in other medical fields. We report six cases of persistent MDR-CE in infertile women who were resistant to all the aforementioned antibiotic agents. The bacterial genera and microbial communities unique to persistent MDR-CE were not identified in their vaginal secretions and/or endometrial fluid. Oral lincomycin administration (14 days, 1500 mg/day) was effective in the eradication of ESPCs in these women. In the embryo transfer cycles following histopathologic confirmation of cure (elimination of ESPCs) of persistent MDR-CE, three out of them had a successful live birth.

Multi-drug-resistant chronic endometritis in infertile women with repeated implantation failure: trend over the decade and pilot study for third-line oral antibiotic treatment

PURPOSE

To evaluate the yearly prevalence and annual transition of multi-drug-resistant-chronic endometritis (MDR-CE) in infertile women with a history of repeated implantation failure (RIF) and to establish the third-line antibiotic treatment regimen against MDR-CE.

METHODS

This retrospective/prospective cohort and pilot study included 3473 RIF women between April 2010 and September 2021. The endometrial stromal plasmacyte density index (ESPDI) was calculated in 3449 CD138-immunostained endometrial sections to evaluate CE. The microbiota in the vaginal secretions and endometrial fluid was compared between 17 patients with MDR-CE and 16 patients with antibiotics-sensitive CE. In a pilot study, oral moxifloxacin (400 mg/day, 10 days, n = 24) or azithromycin (500 mg/day, 3 days, n = 24) was administered to eligible patients with MDR-CE.

RESULTS

From April 2010 to March 2020, CE was detected in 31.4% of RIF women and MDR was detected in 7.8% of CE. While the prevalence of CE was stable for a decade, MDR in CE increased steadily (OR 8.27, 95% CI 2.58-26.43, p trend < 0.001). The bacterial species/communities unique to MDR-CE were not found. The histopathologic cure rate of MDR-CE was similar between the moxifloxacin and azithromycin groups (79.2% vs 75.0%, OR 1.27, 95% CI 0.32-4.89, p value 0.73), as well as reproductive outcomes in subsequent embryo transfer cycles.

CONCLUSION

In RIF women, MDR in CE increased over the decade. As a third-line treatment for MDR-CE, azithromycin may have a clinical advantage due to its shorter time administration periods.

CLINICAL TRIAL NUMBER

ClinicalTrials.gov Identifier: UMIN-CTR 000029449/000031909.

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

PURPOSE

This study aims to assess whether antibiotic therapy for chronic endometritis (CE) could improve subsequent IVF outcomes in patients with recurrent implantation failure (RIF).

METHODS

Studies that explore CE treatment in patients with RIF were retrieved from PubMed, EMBASE, Wanfang, and Google Scholar up to Jan 31, 2022. All retrieved studies were selected according to the inclusion and exclusion criteria. The main outcome measures include implantation rate (IR), clinical pregnancy rate (CPR), ongoing pregnancy rate/live birth rate (OPR/LBR), and miscarriage rate (MR). Odds ratios (ORs) were analyzed for pregnancy outcomes with a 95% confidence interval (CI).

RESULTS

Nine articles were enrolled in this study. Patients receiving oral antibiotic administration (OAA) did not show any advantage over patients without CE with regard to IR, OPR/LBR, and MR, but they showed a higher CPR. Patients with cured CE after OAA therapy had significantly higher CPR, IR, and OPR/LBR compared with patients without CE. Patients with persistent CE after OAA therapy had significantly lower IR, CPR, and OPR/LBR compared with patients without CE. Patients with cured CE had significantly higher IR, CPR, and OPR/LBR compared with persistent CE patients.

CONCLUSIONS

Antibiotic treatment may improve the pregnancy outcomes of RIF patients in subsequent IVF cycles only if the condition of CE is confirmed cured in a control biopsy afterwards. Otherwise, no sufficient evidence has shown improvements in clinical outcomes in RIF patients with persistent CE.

Investigation of the Relationship between Chronic Endometritis Manifestations under Hysteroscope and CD138 Expression

Methods

This study was performed to retrospectively analyze clinical cases of 523 CE patients from January 2018 to June 2020 that were confirmed by hysteroscopy before in vitro fertilization. Based on manifestations of CE under hysteroscopy, the cases were divided into three cohorts, i.e., hyperemia cohort where the patients had diffuse endometrium hyperemia; endometrial micropolyp cohort, and endometrial stroma edema and hyperplasia cohort. Small amount of endometrial tissue was collected from the patients, and CD138 IHC examination was performed. According to the results of CD138 IHC, positive patients were given antibiotic treatment (doxycycline 100 mg BID orally for 14 days), and hysteroscopy was performed again after treatment to check the efficacy of antibiotics.

Results

In the comparison of overall status for all patient cohorts, infertility type, BMI, bFSH, bLH, bP, bT, PRL, AMH, and CA125 were varied markedly across all cohorts (P < 0.05), with predominant incidences of polycystic ovary syndrome (PCOS) peaking within hyperemia cohort. Incidence/diagnostic rate for CD138 within hyperemia cohort was 10.06%, which was lower than the 63.16% in micropolyp cohort and 74% in edema and hyperplasia cohort (P < 0.05). No major variation existed within CD138 across micropolyp cohort/edema and hyperplasia cohort (P > 0.05). After CD138-positive CE patients were treated with antibiotics, the effective rate (0/16) within hyperemia cohort was lower than micropolyp cohort (73.61%, 53/72) and edema and hyperplasia cohort (83.24%, 154/185) (P < 0.05). The effective rate across micropolyp cohort/edema and hyperplasia cohort was not significantly different (P > 0.05).

Conclusion

Cases of diffuse endometrial hyperemia under hysteroscope had the lowest positive rate of CD138, and the effect of antibiotic treatment on these patients was poor. The positive rate of CD138 in patients with endometrial micropolyps and endometrial stroma edema and hyperplasia under hysteroscope was high, and the effect of antibiotic treatment was better.

Risk of spontaneous abortion after antibiotic therapy for chronic endometritis before in vitro fertilization and intracytoplasmic sperm injection stimulation

OBJECTIVE

To investigate whether cured chronic endometritis (CE) from antibiotic treatment would be associated with a higher risk of spontaneous abortion in the following in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment.

DESIGN

Prospective cohort study.

SETTING

Tertiary reproductive medicine center.

PATIENT(S)

Patients with infertility who underwent a routine hysteroscopy underwent an IVF/ICSI stimulation between January 1, 2019, and December 31, 2020. Women with CE (N = 338) underwent antibiotic therapy, and the assisted reproductive outcomes were then compared with women without CE (N = 7,962).

INTERVENTION(S)

Chronic endometritis was diagnosed through hysteroscopy and confirmed by histology and immunohistochemistry for CD138.

MAIN OUTCOME MEASURE(S)

Spontaneous abortion rate after the initial embryo transfer.

RESULT(S)

A total of 7,218 patients underwent embryo transfer, with 330 in the cured CE group and 6,888 in the non-CE group. Women with cured CE had a higher rate of spontaneous abortion than did those without CE (11.8% vs. 9.2%; crude odds ratio [OR], 1.32 [0.94, 1.86]), and this difference was statistically significant after adjusting for confounding variables (adjusted OR, 1.49 [1.01, 2.19]). The live birth rate was 43.9% in the cured CE group and 50.5% in the non-CE group (crude OR, 0.77 [0.62, 0.96]; adjusted OR, 0.73 [0.59, 0.92]). The incidence of clinical pregnancy did not differ significantly between the 2 groups (56.1% vs. 60.0%; crude OR, 0.85 [0.68, 1.06]; adjusted OR, 0.83 [0.66, 1.03]). Sensitivity analyses stratified by initial fresh- or frozen-thawed embryo transfer cycles resulted in similar results.

CONCLUSION(S)

Chronic endometritis cured with antibiotic therapy was associated with an increased risk of spontaneous abortion among women undergoing IVF/ICSI treatment. The interpretation of the findings is limited by a potential confounding bias.

Endometrial polyp is associated with a higher prevalence of chronic endometritis in infertile women

OBJECTIVE

To assess the prevalence of chronic endometritis (CE) among infertile women with endometrial polyps (EP).

METHODS

From June 2017 to October 2021, 583 patients in the polyp group (group A-group A1: single-polyp group, 322 patients; group A2: multiple-polyp group, 261 patients) and 4534 patients in the non-polyp group (group B) were included in this retrospective study. Hysteroscopic polypectomy was performed in group A. Endometrial biopsy and CD138 immunohistochemistry staining for specimens was carried out in all groups.

RESULTS

Prevalence of CE was significantly higher in group A than in group B (45.28% vs. 27.94%, P < 0.001). A significantly higher prevalence of CE was found in group A1 and group A2 compared with group B (42.24% vs. 27.94%, P < 0.001; 49.04% vs. 27.94%, P < 0.001; respectively). No significant difference in the comparison of CE prevalence was found between group A1 and group A2. Similar results were achieved in the subgroup analysis among patients aged 40 years or older and patients younger than 40 years.

CONCLUSION

EP, either single EP or multiple EP, positively correlates with CE. The prevalence of CE was similar between the single-polyp group and the multiple-polyp group.

Overexpression of hypoxia-inducible factor 1α and excessive vascularization in the peri-implantation endometrium of infertile women with chronic endometritis

OBJECTIVE

Chronic endometritis (CE) contributes to impaired endometrial receptivity and is closely associated with poor in vitro fertilization (IVF) outcomes. However, the mechanisms underlying CE are unclear. Here, we investigated the role of the hypoxic microenvironment and endometrial vascularization in the peri-implantation endometrium of infertile women with CE.

METHODS

This retrospective study involved 15 fertile women and 77 infertile patients diagnosed with CE based on CD138+ ≥1/10 high-power fields (HPFs). The CE patients were divided into Group 1 (CD138+ 1-4/10 HPFs, 53 cases) and Group 2 (CD138+ ≥5/10 HPFs, 24 cases). The expression levels of hypoxia-inducible factor 1α (HIF1α), vascular endothelial growth factor A (VEGFA), and vascular endothelial growth factor receptor 2 (VEGFR2) in peri-implantation endometrium were assessed by qRT-PCR and western blot analyses. Spatial levels of HIF1α, VEGFA, and VEGFR2 in various endometrial compartments was determined using immunohistochemistry and H-score analysis. Microvascular density (MVD) was determined using CD34 staining and scored using Image J. Finally, we used qRT-PCR to assess changes in the expression of HIF1α, VEGFA, and VEGFR2 in CE patients after treatment with first-line antibiotics.

RESULTS

Relative to Group 1 and control group, during the implantation window, protein and mRNA levels of HIF1α, VEGFA, and VEGFR2 were markedly high in Group 2 (P<0.05). H-score analysis showed that HIF1α, VEGFA, and VEGFR2 in the luminal, glandular epithelium, and stromal compartments were markedly elevated in Group 2, comparing to control group and Group 1 (P<0.05). Moreover, markedly elevated MVD levels were observed in Group 2. Notably, the above indexes did not differ significantly in the control group versus Group 1. Treatment with antibiotics significantly suppressed the endometrial HIF1α and VEGFA levels in CE-cured patients.

CONCLUSIONS

Here, we for the first time report the upregulation of HIF1α, VEGFA, and VEGFR2, as well as excessive endometrial vascularization in the peri-implantation endometrium of CE patients. Our findings offer new insights into reduced endometrial receptivity in CE-associated infertility.