Association Between Vaginal Gardnerella and Tubal Pregnancy in Women With Symptomatic Early Pregnancies in China: A Nested Case-Control Study

The early diagnosis and treatment of ectopic pregnancy (EP) remains a major challenge. Despite a known link between vaginal microbiota and female reproductive health, few studies have focused on the association between vaginal microbiota and pregnancy location. This nested case-control study aimed to characterize the vaginal microbiota in tubal pregnancy (TP) among symptomatic women in early pregnancy. Women with symptomatic early pregnancy of unknown location (PUL) were included in this study. 16S rDNA gene sequencing was performed to assess vaginal microbial diversity and relative abundance. Machine learning and multivariate logistic regression were also used to evaluate the association between Gardnerella and TP. The results indicate that the vaginal microbiome in TP was more diverse (Shannon, p < 0.05) and was different in composition to that of women with intrauterine pregnancy (IUP) (weighted Unifrac, R = 0.08, p = 0.01). The genus Gardnerella was significantly enriched in TP. The XGBoost analysis was able to classify Gardnerella-induced TP more reliably (AUC = 0.621). Moreover, after adjusting potential confounders, our results indicate a robust association between Gardnerella and TP (as a continuous variable, adjusted OR: 12.0, 95% CI: 2.1–67.4, p < 0.01; as a categorical variable (≥0.85%), and adjusted OR: 4.2, 95% CI: 2.0–8.8, p < 0.01). In conclusion, we found that higher virginal Gardnerella levels were associated with TP in women with symptomatic early pregnancy.

Dysbiosis of vaginal microbiota associated with persistent high-risk human papilloma virus infection

Background The status of vaginal microbiota in persistent high-risk human papilloma virus (HR-HPV) infection is unclear. The present work aimed to identify the vaginal microbiota of persistent HPV infection and explore the possible underlying microbiota factors. Methods A total of 100 women were recruited in this study, of which 28 presented HR-HPV persistent infection (P group), 30 showed clearance of any subtype of HR-HPV (C group), and 42 had no history of any HR-HPV infection (NC group). The vaginal microbiota and the community structure of the three groups were compared based on the 16S rRNA sequencing of the V3–V4 region. The microbiota diversity and differential analysis were carried out to detect the potential factors associated with HR-HPV infection. Results P and C groups showed an increase of Firmicutes and Actinobacteriota but a decrease in Proteobacteria compared to the NC group. The Chao1 index indicated that the microbial richness of the NC group was greater than C group (P < 0.05).The principal co-ordinate analysis(PCoA) revealed differences between the NC and P/C groups.The linear discriminant analysis effect size (LEfSe) method indicated that Proteobacteria phylum was significantly different in the mean relative abundance in the NC group,but the P and C groups did not show such indicative taxa. The Wilcox rank-sum test indicated that the Bifidobacterium (P = 0.002) and Lactobacillus (P = 0.005) of the C group were in a high mean relative abundance compared to the NC group. Conclusions The persistent HR-HPV infection is associated with dysbiosis of the vaginal microbiota. Microbiome regulation with Bifidobacteria and Lactobacillus may affect the clearance of HPV.

Age-related changes, influencing factors and crosstalk between vaginal and gut microbiota: a cross-sectional comparative study of pre- and postmenopausal women

Objective: The ideal vaginal environment is maintained by Lactobacillus species, which keep the vagina clean and free of infections, including sexually transmitted diseases and human papilloma virus infection. Other reported health benefits of Lactobacillus include a favorable impact on fertility and immunity, leading to a reduced risk of gynecological malignancies. Age-related decline in estrogen affects the population of Lactobacillus, leading to dominance of pathogenic flora and increased diversity in vaginal microbiota. In this study, we compared the differences between the vaginal microbiota of premenopausal and postmenopausal women. In addition, we examined the relationships between vaginal and gut microbiota, as well as their relationships to sex hormones and equol producing ability. Methods: This was a cross-sectional study of 35 premenopausal and 35 postmenopausal women, ranging from 27 to 76 years of age. We compared parameters such as the composition of the gut and vaginal microbiota, vaginal pH, sex hormones in the blood (estradiol and follicular stimulating hormone), and urinary equol concentration. Results: In the vaginal microbiota of premenopausal women, Lactobacillus species constituted approximately 71.98%, and pathogenic flora constituted approximately 16.87%. They were 10.08% and 26.78%, respectively, in the vaginal microbiota of postmenopausal women. Therefore, the proportion of Lactobacillus was significantly low, whereas microbial diversity and vaginal pH were significantly high (p<0.0001) in postmenopausal women. The compositions of the vaginal microbiota were significantly different in pre- and postmenopausal women. However, such differences were not noticeable in the gut microbiota. Urinary equol production had no significant correlation with vaginal microbiota, although it had significant relationships with gut microbiota in postmenopausal women. There were significant correlations among bacterial species in the gut and vaginal microbiota, especially in postmenopausal women. In both groups, the proportions of vaginal Lactobacillus were inversely correlated with vaginal microbial diversity and vaginal pH. Conclusion: Postmenopausal women had significantly low lactobacillus and high pathogenic flora in their vaginal flora, whereas such age-related differences were not identified in gut microbiota. There were significant correlations among the bacterial species inhabiting the gut and vaginal microbiota, especially in postmenopausal women, indicating potential crosstalk between each other.

Composition and Stability of the Vaginal Microbiota of Pregnant Women With Inflammatory Bowel Disease

Background Inflammatory bowel disease (IBD) is common in women of childbearing years, and active IBD during pregnancy is associated with increased rates of preterm delivery and low-birth-weight newborns. Changes in the vaginal microbiome have been associated with preterm delivery. We aimed to determine the taxonomic composition of the vaginal microbiota at 3 time points during pregnancy in a population of women with IBD. Methods Participants were recruited from the patient registry of the Preconception and Pregnancy IBD Clinic at Royal University Hospital in Saskatoon, Canada. Self-collected vaginal swabs were obtained from patients at each trimester. Microbiota profiles were created by cpn60 amplicon sequencing. Results We characterized the vaginal microbiota of 32 pregnant participants with IBD (33 pregnancies) during each trimester. A total of 32 of 33 pregnancies resulted in a live birth with 43.8% (n = 14 of 32, 2 missing) by caesarean section; 2 of 32 were preterm. Microbiota compositions corresponded to previously described community state types, with most participants having microbiota dominated by Lactobacillus crispatus. In 25 of 29 participants in which samples were available for more than 1 time point, there was no change in the community state type over time. Prevalence of Mollicutes (Mycoplasma and/or Ureaplasma) was significantly higher in pregnant participants with IBD than in a previously profiled cohort of 172 pregnant women without IBD who delivered at term. Conclusions The vaginal microbiome of participants with IBD was stable throughout pregnancy. Prevalence of Mollicutes, which has been associated with preterm delivery, warrants further study in this patient group.

The association between female reproductive tract microbiota and recurrent pregnancy loss: a nested case-control study

Objective To study the associations of endometrial and vaginal microbiota with recurrent pregnancy loss (RPL). Design A nested case-control study. Setting Helsinki University Hospital, Finland. Population Women with two or more consecutive pregnancy losses (n=47) and healthy control women without a history of pregnancy loss (n=39). Methods The endometrial and vaginal microbiota compositions, analysed using 16S rRNA gene amplicon sequencing, were compared between RPL women and controls, and between individual vaginal and endometrial samples. The mycobiota composition was analysed using internal transcribed spacer 1 amplicon sequencing for a descriptive summary. The models were adjusted for confounding variables BMI, age, and parity, and FDR-corrected P-values (q-values) were used to define nominal statistical significance at q < 0.05. Main outcome measures Mean relative microbial abundances. Results Lactobacillus crispatus was less abundant in the RPL endometrial samples compared to controls (mean relative abundance 17.2% vs. 45.6%, q = 0.04). Gardnerella vaginalis was more abundant in RPL women than in controls in both endometrial (12.4% vs. 5.8%, q < 0.001) and vaginal samples (8.7% vs. 5.7%, q < 0.01). The individual vaginal and endometrial microbial composition correlated strongly (R = 0.85, P < 0.001). Fungi were detected in 22% of the endometrial and 36% of the vaginal samples. Conclusions Unfavourable reproductive tract microbiota was associated with RPL and may represent a novel risk factor for pregnancy losses.

Microbiological Study of Vaginal Microbiota and Endometrium in Women with Chronic Endometritis

The research objective was to study the spectrum of the vagina and endometrium microorganisms in women with chronic endometritis (CE) in order to take adequate therapeutic measures. Methods and Results: We did a cross-sectional study in 47 women (average age of 35.38±5.19 years) with histologically confirmed CE. The vaginal microbiota and endometrial biopsies were assessed using microbiological research methods in accordance with the medical technology "Integral assessment of the state of the vaginal microbiota." To identify the share of different types of microorganisms in the structure of the biocenosis, the coefficient of constancy of the species (C) was used. Only 19% of patients had a titer of Lactobacillus spp. within the age norm, while the deficit was observed in 80% of women. Among the representatives of Enterobacteriaecae, Escherichia coli and Klebsiella aerogenes were sown, which are considered to be random species (C=11% and C=2.1%, respectively). The average titer for E. coli was 3.6±1.3 lg CFU/swab and for K. aerogenes - 2.14 lg CFU/swab. An atypical variant of E. coli with hemolytic properties was found in only one sample. All isolates of the genus Staphylococcus were also random species (C did not exceed 25%). Coagulase-negative staphylococci (CoNS) were detected in 7 patients (C=15%), while the average titer was 2.1±0.4 lg CFU/swab. S. aureus was isolated from only one patient at a titer of 5 lg CFU/swab. Corynebacterium spp. were isolated in 11% of cases (C = 11% - random species), in a titer of 3.2±0.8 lg CFU/swab. Enterococcus spp. also belonged to random species (C=23.4%). At the same time, E. faecalis was inoculated in 19% of cases and E. faecium was sown in 4.3%, the average titer of which was 3.1±0.9 and 5 lg CFU/swab. Streptococcus spp. were recorded in only one case at a concentration of 5 lg CFU/swab. Fungi of the Candida were isolated as a random species in 8.5% of cases. The growth of microorganisms in endometrial samples was obtained only in 3 examined women with CE (6.4% of cases). The endometrial microbiota were represented only by random species, for which the C index ranged from 2.1% to 4.3%. Conclusion: The microbiological study of the microbiota of vaginal discharge showed the presence of dysbiotic disorders with a significant deficiency of lactobacilli (80%) without the dominance of representatives of the Lactobacillus spp. In the structure of opportunistic microflora, Escherichia coli, coagulase-negative staphylococcus, Enterococcus spp., and E. faecalis prevailed as random species. Representatives of the microbiota in endometrial biopsies were identified only in 6.4% of cases, and are represented by random species.

Vaginal microbiota of American Indian women and associations with measures of psychosocial stress

Molecular-bacterial vaginosis (BV) is characterized by low levels of vaginal Lactobacillus species and is associated with higher risk of sexually transmitted infections (STI). Perceived psychosocial stress is associated with increased severity and persistence of infections, including STIs. American Indians have the highest rates of stress and high rates of STIs. The prevalence of molecular-BV among American Indian women is unknown. We sought to evaluate measures of psychosocial stress, such as historic loss (a multigenerational factor involving slavery, forced removal from one’s land, legally ratified race-based segregation, and contemporary discrimination) and their association with the vaginal microbiota and specific metabolites associated with BV, in 70 Northwestern Plains American Indian women. Demographics, perceived psychosocial stressors, sexual practices, and known BV risk factors were assessed using a modified version of the American Indian Service Utilization, Psychiatric Epidemiology, Risk and Protective Factors Project survey. Self-collected mid-vaginal swabs were profiled for bacterial composition by 16S rRNA gene amplicon sequencing and metabolites quantified by targeted liquid-chromatography mass spectrometry. Sixty-six percent of the participants were classified as having molecular-BV, with the rest being either dominated by L. crispatus (10%) or L. iners (24%). High levels of lifetime trauma were associated with higher odds of having molecular-BV (adjusted Odds Ratio (aOR): 2.5, 95% Credible Interval (CrI): 1.1–5.3). Measures of psychosocial stress, including historic loss and historic loss associated symptoms, were significantly associated with lifestyle and behavioral practices. Higher scores of lifetime trauma were associated with increased concentrations of spermine (aFC: 3.3, 95% CrI: 1.2–9.2). Historic loss associated symptoms and biogenic amines were the major correlates of molecular-BV. Historical loss associated symptoms and lifetime trauma are potentially important underlying factors associated with BV.

Comparison of Female Genital Tract Cytokine and Microbiota Signatures Induced by Initiation of Intramuscular DMPA and NET-EN Hormonal Contraceptives - a Prospective Cohort Analysis

BackgroundCervicovaginal inflammation, bacterial microbiota and hormonal contraceptives all influence sexual and reproductive health. To date, the effects of intramuscular depo-medroxyprogesterone acetate (DMPA-IM) versus injectable norethisterone enanthate (NET-EN) on vaginal microbiota or cytokines have not been compared back-to-back, although in-vitro data suggest that DMPA-IM and NET-EN have different pharmacokinetic and biologic activities. This study aimed at comparing the effects of DMPA-IM versus NET-EN initiation on cervicovaginal cytokines and microbiota in women at high risk for sexually transmitted infections (STIs) assigned to the respective contraceptives.MethodsWe collected socio-demographic characteristics and vaginal samples from women initiating DMPA-IM (ECHO Trial; n = 53) and NET-EN (UChoose Trial; n = 44) at baseline and after two consecutive injections to assess cytokine concentrations by Luminex, vaginal microbiota by 16S rRNA gene sequencing, STIs, bacterial vaginosis (BV) and candidiasis.ResultsCytokine concentrations did not change significantly after initiating DMPA-IM or NET-EN, although NET-EN versus DMPA-IM-associated profiles were distinct. While the abundance of bacterial taxa associated with optimal and non-optimal microbiota fluctuated with DMPA-IM use, overall community composition did not significantly change with either contraceptive. HSV-2 serology, chlamydial infection, gonorrhoea and candidiasis did not influence the associations between contraceptive type and cervicovaginal cytokines or microbiota.ConclusionsBoth DMPA-IM and NET-EN use did not lead to broad inflammatory or microbiota changes in the female genital tract of sub-Saharan African women. This suggests that NET-EN is likely a viable option for contraception in African women at high risk of BV and STIs.

Impact of Dapivirine and Placebo Vaginal Rings on the Microbiota of Adolescent, Lactating, and Postmenopausal Females

Background A 25 mg dapivirine vaginal ring has been demonstrated to reduce risk of HIV acquisition in nonpregnant adult women. In this secondary analysis of studies conducted in US adolescent, lactating, and postmenopausal females, vaginal microbiota was assessed prior to and after ring use, and between dapivirine and placebo ring users. Methods Vaginal fluid swabs were collected before and after product use for the evaluation of microbiota using Nugent’s criteria, quantitative culture, and qPCR. Results Vaginal ring use did not impact bacterial vaginosis prevalence among the three populations and was associated with minimal shifts in microbiota. Adolescents in both arms demonstrated an increased prevalence of Lactobacillus crispatus and a decrease in quantity of Megasphaera lornae. Postmenopausal active and placebo ring users demonstrated an increased prevalence of lactobacilli and non-albicans yeast while dapivirine ring users demonstrated an increased prevalence of Candida albicans, and increased quantity of Group B Streptococcus (GBS) and non-albicans yeasts. Prevotella species were increased in lactating women while P. timonensis increased in prevalence and concentration among adolescent and postmenopausal women and P. bivia increased in prevalence among adolescent dapivirine ring users. Conclusions Dapivirine vaginal ring use was associated with minimal changes in the vaginal microbiota that are likely not clinically significant.

Large-scale characterisation of the pregnancy vaginal microbiome and sialidase activity in a low-risk Chinese population

Vaginal microbiota-host interactions are linked to preterm birth (PTB), which continues to be the primary cause of global childhood mortality. Due to population size, the majority of PTB occurs in Asia, yet there have been few studies of the pregnancy vaginal microbiota in Asian populations. Here, we characterized the vaginal microbiome of 2689 pregnant Chinese women using metataxonomics and in a subset (n = 819), the relationship between vaginal microbiota composition, sialidase activity and leukocyte presence and pregnancy outcomes. Vaginal microbiota were most frequently dominated by Lactobacillus crispatus or L. iners, with the latter associated with vaginal leukocyte presence. Women with high sialidase activity were enriched for bacterial vaginosis-associated genera including Gardnerella, Atopobium and Prevotella. Vaginal microbiota composition, high sialidase activity and/or leukocyte presence was not associated with PTB risk suggesting underlying differences in the vaginal microbiota and/or host immune responses of Chinese women, possibly accounting for low PTB rates in this population.