Background: Cervicovaginal inflammation has been linked to negative reproductive health outcomes including the acquisition of HIV, other sexually transmitted infections, and cervical carcinogenesis. While changes to the vaginal microbiome have been linked to genital inflammation, the molecular relationships between the functional components of the microbiome with cervical immunology in the reproductive tract are understudied, limiting our understanding of mucosal biology that may be important for reproductive health. Results: In this study, we used a multi’-omics approach to profile cervicovaginal samples collected from 43 Canadian women to characterize host, immune, functional microbiome, and metabolome features of cervicovaginal inflammation. We demonstrate that inflammation is associated with lower amounts of L. crispatus and higher levels of cervical antigen-presenting cells (APCs). Proteomic analysis showed an upregulation of pathways related to neutrophil degranulation, complement, and leukocyte migration, with lower levels of cornified envelope and cell-cell adherens junctions. Functional microbiome analysis showed reductions in carbohydrate metabolism and lactic acid, with increases in xanthine and other metabolites. Bayesian network analysis linked L. crispatus with glycolytic and nucleotide metabolism, succinate and xanthine, and epithelial proteins SCEL and IVL as major molecular features associated with pro-inflammatory cytokines and increased APCs. Conclusions: This study identified key molecular and immunological relationships with cervicovaginal inflammation, including higher APCs, bacterial metabolism, and proteome alterations that underlie inflammation. As APCs are involved in HIV transmission, parturition, and cervical cancer progression, further studies are needed to explore the interactions between these cells, bacterial metabolism, mucosal immunity, and their relationship to reproductive health.

Lichen sclerosus is a chronic inflammatory condition of unknown etiology that affects the genital and extragenital skin, which can lead to sexual dysfunction and has been associated with vulvar cancer. The vaginal microbiome has a critical role in gynecologic health, but little is known about the microbiome in lichen sclerosus. This study investigated the vaginal and vulvar microbiomes of 27 post-menopausal women with lichen sclerosus. The most abundant genera detected in the vaginal microbiome were Lactobacillus, Gardnerella, and Anaerococcus, while Lactobacillus, Anaerococcus, and Staphylococcus were the most abundant in the vulvar microbiome. The vaginal samples clustered into two main groups, Lactobacillus dominant (n = 6, > 50% microbiome Lactobacillus) and polymicrobial (n = 21) with no dominant genus. The vulvar samples were mainly polymicrobial (n = 25). Actinomyces, Anaerococcus, and Ezakiella in the vaginal microbiome and Actinomyces and Ezakiella in the vulvar microbiome were significantly associated with lichen sclerosus symptoms (adjusted p < 0.05). In this population of post-menopausal women with lichen sclerosus the majority have diverse, non-Lactobacillus dominant microbiomes, which is considered less optimal for gynecologic health based on studies of pre-menopausal women. Actinomyces, Ezakiella, and Anaerococcus were associated with lichen sclerosus symptoms. Understanding the role of these bacteria in lichen sclerosus pathogenesis will be an essential future investigation.

Infertility, defined as the inability to establish a clinical pregnancy after a year of regular, unprotected sexual intercourse, impacts 8%–12% of couples worldwide. Many of these couples turn to in vitro fertilization (IVF) to build their families. The success rate of IVF procedures is variable, with estimates of up to 40% of embryo transfers being unsuccessful. Herein we review the existing literature on the role of the female and male urogenital microbiomes and genital inflammation on fertility and IVF outcomes. We discuss the microbiome across the female reproductive tract (FRT) and identify associations with female infertility, female genital tract inflammation, and success of IVF procedures. We also discuss the male urogenital microbiome and the associations between microbial taxa, genital inflammation, and male fertility parameters. Finally, we consider microbial transfer within couples and the impact this may have on fertility and the success of IVF procedures.

Problem: Aging is characterized by a general dysregulation of systemic immune responses that increases susceptibility to infections and malignancies. Immune cells in the female genital tract (FGT) are regulated by sex hormones, but little is known about the impact of aging and menopause on immunology in the FGT.Method of Study: This study conducted an age‐focused sub‐analysis of cervicovaginal samples collected from 47 women enrolled in the Vaginal Mucosal Systems study in Winnipeg, Canada. Paired cervicovaginal lavage and cervical cytobrush were collected and analyzed by Luminex cytokine array, mass spectrometry based metaproteomics, metabolomics, and high dimensional flow cytometry.Results: The median age of study participants was 38 (range 19–88), with 12 over the age of 50. Increasing age was significantly correlated with increased cervicovaginal inflammation, including inflammatory cytokine MIP‐1β (r = 0.335, p = 0.023), and activated T cells (CD4+HLA‐DR+ r = 0406, p = 0.009; CD8+HLA‐DR+ r = 0.399, p = 0.010; CD8+CD38+HLA‐DR+ r = 0.386, p = 0.013). Proteomic analysis of cervicovaginal mucus identified 925 human proteins, with 108 (11.7%) significantly correlated with age. Pathway analysis indicated biofunctions related to immune response, migration, and myeloid cell phagocytosis increased with age. Interestingly, neutrophil related pathways decreased with age, including G‐CSF (r = −0.396, p = 0.006) and reactive oxygen species (z‐score = −2.607, p = 2.31E‐4). Vaginal Lactobacillus crispatus, a species associated with mucosal health, significantly decreased with age (r = −0.340, p = 0.022), with participants over the age of 50 more likely to have non‐Lactobacillus dominant microbiomes compared to those under 40.Conclusions: Together, our data suggests that there is an increase in cervicovaginal inflammation and a decrease in L. crispatus that occurs with aging.

Objective: Bacterial vaginosis is a dysbiosis of the vaginal microbiome, typically characterized by a loss of Lactobacillus. Lactobacillus plays a crucial role in vaginal immunity and protection against sexually transmitted infections. Herpes simplex virus 2, the primary cause of genital herpes, impacts 13% of people worldwide. We undertook this systematic review and meta-analysis to examine the risk of herpes simplex virus 2 acquisition in women with bacterial vaginosis. Secondarily, we examined the impact of bacterial vaginosis on herpes simplex virus 2 shedding, reactivation, and symptoms. Data sources: We searched PubMed, EMBASE, Cochrane, Web of Science, Google Scholar, and ClinicalTrials.gov for articles published before 1 July 2023 for microbiome and herpes simplex virus type 2. Studies were limited to human subjects and the English language. An updated search was performed in January 2026. This study was registered on PROSPERO (CRD42023439139). Methods of study selection: Studies on non-pregnant, reproductive-aged cisgender women that diagnosed bacterial vaginosis by Amsel Criteria, Nugent Scoring or used molecular techniques, and those that detected herpes simplex virus 2 by serological assay or PCR testing were included. Our search identified 863 results with four publications eligible for inclusion. For our secondary outcomes, 40 results were identified regarding herpes simplex virus 2 shedding, with two publications eligible for inclusion, which did not meet our threshold for meta-analysis. There were 21 results identified for herpes simplex virus 2 reaction and 115 results for herpes simplex virus 2 symptoms, with no articles being eligible for inclusion. Tabulation, integration, and results: Quality assessment was performed following data extraction using the quality assessment scales from the Joanna Briggs Institute. Results were extracted, and the pooled hazard ratio was calculated with 95% confidence interval. A total of 1906 women were included in this analysis, and 255 acquired herpes simplex virus 2. The pooled unadjusted hazard ratios produced an effect size of 1.91, (95% confidence interval 1.4649–2.4980), and a p-value of <0.0001, while the pooled adjusted hazard ratios produces an effect size of 1.85, (95% confidence interval of 1.3556–2.5162), and a p-value of 0.0001 indicating that bacterial vaginosis is associated with a increased risk of herpes simplex virus 2 acquisition. Conclusions: This systematic review with meta-analysis indicates that bacterial vaginosis is associated with a significantly increased risk (91% unadjusted, 85% adjusted) of herpes simplex virus 2 acquisition, indicating that bacterial vaginosis treatment may reduce herpes simplex virus 2 acquisition. A notable limitation of these findings is the relatively small number of studies eligible for inclusion in this systematic review and meta-analysis.

Structured Background: Endometriosis is a chronic, estrogen-dependent disease characterized by the presence of endometrial-like tissue growing outside the uterus. The molecular and clinical heterogeneity of endometriosis complicate diagnostic and treatment options -- diagnostic delays of seven to ten years are common and therapies often lack long-term efficacy. Estrogen signaling and estrogen receptor beta (ERβ) expression is thought to be increased in endometriosis, contributing to increased cell proliferation in lesions. The “ERβ dominance hypothesis” is a prevailing hypothesis in the field, setting ERβ as a high-priority therapeutic target. If effectively modulated, ERβ could be the first therapy to directly target lesion biology, rather than only managing symptoms. Objective(s): We aimed to characterize ERβ’s expression in endometriosis by cell type and evaluate its therapeutic relevance, primarily assessing the validity of the ERβ dominance hypothesis. Study Design: We reanalyzed scRNAseq data from eight previously published studies. Our final filtered dataset included 557,061 cells, the largest endometriosis single cell atlas ever constructed. We quantified gene expression levels of ESR1 and ESR2, which encode ERɑ and ERβ respectively, across each tissue and cell type, to identify cell-type specific drivers of ESR2/ERβ expression across diseased and healthy tissues. To characterize the differences between cells that uniquely express ESR1 versus those that uniquely express ESR2, we performed differential gene expression and pathway enrichment analyses. Results: Count and distribution analyses revealed no significant ESR2/ERβ dominance in any cell or tissue type by Fisher’s Exact Tests and Wilcoxon Rank Sum Tests. Differential gene expression and pathway enrichment analyses suggest distinct roles of each estrogen receptor isoform. Conclusion(s): Overall, our results argue against a simplified model of ERβ dominance and instead propose a dual-isoform and cell and tissue-specific framework for understanding estrogen receptor signaling in endometriosis. These findings hold important implications for future therapeutic strategies. Specifically, treatments that target ERβ alone may fail to account for the functional role and relative abundance of ERα. In the future, therapeutic approaches that consider isoform-specific, tissue-specific, and cell-specific expression patterns may prove most effective in reducing recurrence and improving outcomes for patients. Condensation page: Tweetable statement: Single cell RNA Sequencing meta-analysis shows estrogen receptor beta is not dominantly expressed in most endometriosis tissues. Estrogen receptor alpha to estrogen receptor beta ratios vary by cell type and tissue type. Each isoform directs cell-type specific behavior in endometriosis and disease-free tissues. AJOG at a Glance: Why was this study conducted? We wanted to characterize estrogen receptor beta’s expression in endometriosis and evaluate its therapeutic relevance. What are the key findings? Estrogen receptor beta is not dominantly expressed in any tissue. Estrogen receptor alpha and estrogen receptor beta have disease- and cell-type specific behaviors. What does this study add to what is already known? It characterizes estrogen receptor isoform expression and signaling by cell type. It also challenges the current estrogen receptor beta dominance hypothesis, meaning estrogen receptor beta may not be a key driver of endometriosis.