Dysbiosis Of Vaginal Microbiota Research Articles

Role of Lactobacillus in Female Infertility Via Modulating Sperm Agglutination and Immobilization.

Infertility has become a common problem in recent decades. The pathogenesis of infertility is variable, but microbiological factors account for a large proportion of it. Dysbiosis of vaginal microbiota is reportedly associated with female infertility, but the influence of normal vaginal microbiota on infertility is unclear. In this review, we summarize the physiological characteristics of the vaginal tract and vaginal microbiota communities. We mainly focus on the bacterial adherence of vaginal Lactobacillus species. Given that the adherent effect plays a crucial role in the colonization of bacteria, we hypothesize that the adherent effect of vaginal Lactobacillus may also influence the fertility of the host. We also analyze the agglutination and immobilization effects of other bacteria, especially Escherichia coli, on ejaculated spermatozoa, and speculate on the possible effects of normal vaginal microbiota on female fertility.

Vaginal Microbial Community Dysbiosis and Associated Outcomes among Women under Contraception at Musasa Health Center, Rwanda

Background: Vaginal microbiota dysbiosis could lead to the vaginal health conditions. This imbalance in vaginal microbiota can be due to a number of factors including contraceptive methods. Objective: This study was carrried out to investigate the vaginal microbiota dysbiosis and associated vaginal health outcomes among women under contraception at Musasa health Center. Materials and Methods: This was a cross sectional study. 56 vaginal swab samples were collected from women enrolled in a family planning program, and transported to INES Ruhengeri clinical microbiology laboratory for vaginal microbial community analysis. The outcomes were evaluated by scheduled interviews. Chi square test was used to evaluate association of microbiota imbalances in the vagina and the vaginal health outcomes. Results: Lactobacilli (92.85%) was the most predominant microorganism observed in the vagina. Outcomes of the vaginal microbiota dysbiosis under different contraceptive regimes were observed. Vaginal microbial community imbalance in different family planning methods was statistically significant (x2 = 36.5, P = 0.049048) to be associated with vaginal health outcomes such as bacterial vaginosis, urinary tract infections, candidiasis and vaginitis. The association with contraceptives contraceptive methods and vaginal microbial community dysbiosis was statistically significant (x2 = 96.2403, P = 0.000491). The Implant for 5 years and Intrauterine device (IUD) were statistically significant (x2 = 28.533, P = 0.002681 and x2 = 27, P = 0.004595 respectively) to contribute to the vaginal microbiota balance. Conclusion: This study established that family planning methods could cause vaginal dysbiosis thereby exposing the vagina to adverse health outcomes and poor reproductive health. Women undergoing family planning should seek medical support if any sign of vaginal infection is observed.

In silico trio biomarkers for bacterial vaginosis revealed by species dominance network analysis

BV (bacterial vaginosis) influences 20%–40% of women but its etiology is still poorly understood. An open question about BV is which of the hundreds of bacteria found in the human vaginal microbiome (HVM) are the major force driving the vaginal microbiota dysbiosis. Here, we recast the question of microbial causality of BV by asking if there are any prevalent ‘signatures’ (network motifs) in the vaginal microbiome networks associated with it? We apply a new framework [species dominance network analysis by Ma & Ellison (2019): Ecological Monographs) to detect critical structures in HVM networks associated with BV risks and etiology. We reanalyzed the 16 s-rRNA gene sequencing datasets of a mixed-cohort of 25 BV patients and healthy women. In these datasets, we detected 15 trio motifs that occurred exclusively in BV patients. We failed to find any of these 15 trio motifs in three additional cohorts of 1535 healthy women. Most member-species of the 15 trio motifs are BV-associated anaerobic bacteria (BVAB), Ravel’s community-state type indicators, or the most dominant species; virtually all species interactions in these trios are high-salience skeletons, suggesting that those trios are strongly connected ‘cults’ associated with the occurrence of BV. The presence of the trio motifs unique to BV may act as indicators for its personalized diagnosis and could help elucidate a more mechanistic interpretation of its risks and etiology. We caution that scarcity of large longitudinal datasets of HVM also limited further verifications of our findings, and these findings require further clinical tests to launch their applications.

The Association Between Vaginal Microbiota Dysbiosis, Bacterial Vaginosis, and Aerobic Vaginitis, and Adverse Pregnancy Outcomes of Women Living in Sub-Saharan Africa: A Systematic Review

Background: Previous studies have described the association between dysbiosis of the vaginal microbiota (VMB) and related dysbiotic conditions, such as bacterial vaginosis (BV) and aerobic vaginitis (AV), and various adverse pregnancy outcomes. There is limited overview of this association from countries in sub-Saharan Africa (SSA), which bear a disproportionally high burden of both vaginal dysbiotic conditions and adverse pregnancy outcomes. This systematic review assesses the evidence on the association between VMB dysbiosis, BV, and AV, and late adverse pregnancy outcomes in women living in SSA.Methods: The Preferred Reporting Items for Systematic Review and Meta-Analysis Statement (PRISMA) guidelines were followed. Three databases [PubMed, Embase (Ovid), and Cochrane] were used to retrieve observational and intervention studies conducted in SSA that associated VMB dysbiosis, BV, or AV and preterm birth/labor/delivery, preterm rupture of membranes (PROM), low birthweight, small for gestational age, intrauterine growth restriction, intrauterine infection, intrauterine (fetal) death, stillbirth, perinatal death, or perinatal mortality.Results: Twelve studies out of 693 search records from five SSA countries were included. One study identified a positive association between VMB dysbiosis and low birthweight. Despite considerable differences in study design and outcome reporting, studies reported an association between BV and preterm birth (7/9), low birthweight (2/6), PROM (2/4), intrauterine infections (1/1), and small for gestational age (1/1). None of the retrieved studies found an association between BV and pregnancy loss (5/5) or intrauterine growth retardation (1/1). At least two studies support the association between BV and PROM, low birthweight, and preterm birth in Nigerian pregnant women. No reports were identified investigating the association between AV and late adverse pregnancy outcomes in SSA.Conclusion: Two of the included studies from SSA support the association between BV and PROM. The remaining studies show discrepancies in supporting an association between BV and preterm birth or low birthweight. None of the studies found an association between BV and pregnancy loss. As for the role of VMB dysbiosis, BV, and AV during pregnancy among SSA women, additional research is needed. These results provide useful evidence for prevention efforts to decrease vaginal dysbiosis and its contribution to adverse pregnancy outcomes in SSA.

Association of the vaginal microbiota with pregnancy outcomes in Chinese women after cervical cerclage

Research questionThe study aimed to investigate the relationship between risk factors associated with vaginal microbiota and outcomes of cervical cerclage. DesignA retrospective cohort study of singleton pregnancies with cervical cerclage was conducted. Before cerclage, participants underwent a vaginal microbiota assay, including morphological examination and functional vaginal microecological analysis using a vaginitis multi-test kit. The chi-squared test and logistic and linear regression analyses were performed to evaluate the associations of various risk factors with maternal and neonatal outcomes. ResultsEighty-five participants were included. The mean interval between cerclage and delivery was 69.4 ± 36.7 days, and 12 (14.1%) of newborns died. A higher grade of vaginal cleanliness, a higher pH, a lower abundance of Lactobacillus spp., a higher sialidase-positive percentage, a higher positive percentage of clue cells, a higher lactobacillary grade, a higher Nugent score and a higher rate of microecological dysbiosis were significantly associated with a poor neonatal outcome and shorter cerclage to delivery intervals (P < 0.001–0.041). Furthermore, sialidase positivity was associated with the highest risk of cervical cerclage failure (odds ratio [OR] 10.469; 95% confidence interval [CI] 1.096–36.087), followed by the presence of bulging membranes (OR 6.400; 95% CI 0.428–15.641) and vaginal microbiota dysbiosis (OR 6.038; 95% CI 0.173–17.072). ConclusionsAn absence of Lactobacillus spp. and some functional factors of vaginal microbiota are potential risk factors that predict subsequent cerclage failure. These findings indicate the potential clinical utility of these factors to predict cervical cerclage failure for managing patient expectations and providing improved postoperative surveillance.

Recovery of Vaginal Microbiota After Standard Treatment for Bacterial Vaginosis Infection: An Observational Study.

Vaginal microbiota dysbiosis and bacterial vaginosis (BV) affect negatively women’s health. Understanding vaginal microbiota fluctuations in BV during and after antibiotic treatment would facilitate accurate decision-making on the treatment regimen, avoid unnecessary antibiotic use, and potentially mitigate recurrence. We investigated vaginal microbiota composition of 30 women with BV before and after 5-day metronidazole treatment and compared the results with 30 healthy women. Vaginal microbiota was assessed by Nugent score and analyzed by 16S rRNA gene sequencing in swabs on baseline Day 1, and on Day 8 and 15, after completion of antibiotic treatment by women with BV. Prior to antibiotic treatment (Day 1), BV-positive women were dominated by Lactobacillus iners (25.8%), Prevotella timonensis/bivia (18.0%), and Gardnerella vaginalis (14.6%), whereas healthy women were dominated by L. iners (37.5%) and Lactobacillus crispatus/acidophilus (19.2%). On Day 8, L. iners abundance increased in BV-treated women being significantly higher compared with healthy women (67.8% vs. 37.5%, p = 0.049). On Day 15, the relative abundance of all microbial taxa was similar between the groups. Vaginal microbiota of women with BV shifted to resemble that of healthy controls after metronidazole. Sequencing analysis provides more in-depth understanding of changes in vaginal microbiota. The role of L. iners in vaginal health and dysbiosis requires further investigations.

Cervical cancer and vaginal microbiota changes.

Microbial changes in vaginal ecosystem may accelerate the process of cervical carcinogenesis. The developed cervical cancer can lead to changes in the vaginal microbiota. The aim of our study is to determine the vaginal microbiota changes at women with FIGO I stage cervical cancer. We conducted an open, single-site survey in the Department of Gynecology of the Military Medical Academy in Sofia, Bulgaria, from 2014 to 2019year. The study included a total of 32 women aged 38-55years with clinical and pathology established cervical cancer (FIGO I stage). The underlying vaginal DNA microbiological test indicated presence or absence of bacterial vaginosis, other vaginal infections or normal vaginal microbiota. Of 32 (100%) women enrolled in our study, 19 (59.4%) was with FIGO IA stage cervical cancer and 13 (40.6%) with IB stage. Disturbances of vaginal microbiota in we found at 23 (71.9%) of women with cervical cancer included in our study. At the rest of 9 (28.1%) women we found out normal vaginal microbiota. Bacterial vaginosis was determined clinically and microbiologically in 15 (46.9%) women enrolled in the study. Aerobic vaginitis caused by Streptococcus species we establish at 4 (12.5%) of women. Trichomonas vaginalis infection have 1 (3.1%) women and Candida Albicans the last one 1 (3.1%) from this group with disturbed vaginal microbial balance. Bacterial dysbacteriosis, characterized by a predominance of Gardnerella vaginalis alone or in complex with other anaerobic bacteria, aerobic vaginitis and other sexually transmitted vaginal pathogens from one side and a concomitant paucity of vaginal Lactobacillus species may be an HPV-dependent cofactor for cervical neoplasia development. Only with this single observation it is difficult to confirm that vaginal microbiota dysbiosis contributes to HPV infection and carcinogenesis.

Bacterial identification of the vaginal microbiota in Ecuadorian pregnant teenagers: an exploratory analysis.

BackgroundBacterial vaginosis (BV) is a microbial imbalance (i.e., dysbiosis) that can produce serious medical effects in women at childbearing age. Little is known, however, about the incidence of BV or vaginal microbiota dysbiosis in pregnant teenagers in low and middle-income countries such as Ecuador. The scope of this exploratory analysis was to study the relationship between epidemiologic and microbial risk factors. Among the microbiology risk factors this study investigated five Lactobacillus species, two of them know in preview studies as microbiology risk factors for BV development (Lactobacillus acidophilus and Lactobacillus iners), and the last three known for being associated with a healthy vaginal tract (Lactobacillus crispatus, Lactobacillus gasseri and Lactobacillus jensenii). In addition, fastidious anaerobes known to be microbial risk factors for BV development in pregnant teenagers were searched as well, more exactly, Gardnerella vaginalis, Atopobium vaginae and Mobiluncus mulieris.MethodsNinety-five healthy adolescent pregnant women, visiting a secondary level hospital in Quito, Ecuador, were enrolled into the study in 2015. The enrolled patients were between 10 to 13 weeks of pregnancy. Four epidemiological risk factors were collected in a survey: age, civil status, sexual partners and condom use. Also, vaginal pH was measured as a health risk factor. DNA was extracted from endocervical and exocervical epithelia from all the patients’ samples. PCR analysis was performed in order to characterize the presence of the eight bacterial species known as risk factors for BV development, targeting three anaerobes and five Lactobacillus species. Univariate and multivariate analysis were performed to identify associated factors for the presence of anaerobic species using logistic regression.ResultsThe 95 vaginal microflora samples of these teenagers were analyzed. Two of the bacterial species known to cause BV: A. vaginae (100%) and G. vaginalis (93.7%) were found in high prevalence. Moreover, the most predominant bacterial Lactobacillus species found in the pregnant teenagers’ vaginal tract were L. crispatus (92.6%), L. iners (89.5%) and L. acidophilus (87.4%). In addition, the average vaginal pH measured in the study population was 5.2, and high pH was associated with the presence of the three-anaerobic species (p = 0.001). Finally, L. jensenii’s presence in the study decreased in 72% the occupation of the three anaerobes.DiscussionThis work identified a high pH as a risk factor for BV anaerobes’ presence in adolescent pregnant women. Moreover, this study identified L. crispatus, L. iners and L. acidophilus to be the most abundant species in our study population. From all fastidious anaerobes analyzed in this study, A. vaginae was present in all pregnant teenagers. To conclude, L. jensenii could be a potential healthy vaginal microbiota candidate in pregnant teenagers and should be further analyzed in future studies.

Local Immunity Status and Apoptosis Reactions in Endometrium of Women with a History of Non-Developing Pregnancy

In order to estimate the status of local immunity of women with a history of non-developing pregnancy, we conducted a research of cytokine-producing cells (CD4+IFN-γ+, CD4+IL-4+) and apoptosis markers (AnV+/ PI--, AnV+/PI+-, AnV-/PI+-cells) in endometrial biopsy material. In addition to this, we studied the number of activated blood mononuclears expressing CD95+ receptor. The research has shown that the development of chronic inflammation in endometrium is associated with anaerobic dysbiosis of vaginal microbiota coupled with impaired production of intracellular cytokines, a cytokine balance shift towards Th1-dependent immune response at the local level and an increase in production of proinflammatory mediators in blood serum. A compensatory reaction limiting the number of activated cells in endometrium is expressed in an increased number of apoptosising mononuclears at different stages of cell death. A decrease in the number of cells demonstrating readiness to programmed cell death in peripheral blood indicates that potentially dangerous activated lymphocytes are preserved in circulation at the system level. Defining the polarization index of cytokineproducing cells and the number of endometrial mononuclears expressing Fas-antigen may be used as additional criteria for early detection of endometrial conditions.