Hormonal contraception decreases bacterial vaginosis but oral contraception may increase candidiasis: implications for HIV transmission

Assessment and Treatment of Vaginitis

Vaginitis is the presenting symptom at millions of office visits each year in the United States. Although treatment of sporadic cases is often straightforward, recurrent cases present both diagnostic and treatment challenges. Molecular diagnostic tests are likely superior to in-office microscopy for most clinicians and most cases. In both recurrent bacterial vaginosis and recurrent vulvovaginal candidiasis, national treatment guidelines recommend an extended treatment duration with one of the first-line agents. In cases in which such treatment is not successful, vaginal boric acid is likely the cheapest and easiest alternative option. New antifungal medications offer additional but limited treatment options. Probiotics are not recommended for prevention of vulvovaginal candidiasis; however, vaginal products containing Lactobacillus crispatus may have promise for recurrent bacterial vaginosis. Trichomoniasis should be treated with a 1-week course of metronidazole; this is the only sexually transmitted infection for which treatment recommendations vary by sex. In cases in which patients do not respond to initial treatment, the diagnosis should be reconsidered, and other potential causes such as desquamative inflammatory vaginitis, genitourinary syndrome of menopause, or vulvodynia should be considered.

A molecular view on the interference established between vaginal Lactobacilli and pathogenic Candida species: Challenges and opportunities for the development of new therapies

Vaginal infectious diseases caused by viruses and bacteria have been linked to the occurrence of dysbiosis, that is, a reduction in the abundance of the normally dominating vaginal Lactobacillus species. Mucosal infections in the vagina and/or vulva caused by Candida species, usually known as vulvovaginal candidiasis (or VVC), are among the leading causes of diseases in the vaginal tract. The existence of a clear link between the occurrence of dysbiosis and the development of VVC is still unclear, although multiple observations point in that direction. Based on the idea that vaginal health is linked to a microbiota dominated by lactobacilli, several probiotics have been used in management of VVC, either alone or in combination with antifungals, having obtained different degrees of success. In most cases, the undertaken trials resorted to lactobacilli species other than those indigenous to the vaginal tract, although in vitro these vaginal species were shown to reduce growth, viability and virulence of Candida. In this paper we overview the role of lactobacilli and Candida in the vaginal micro- and myco-biomes, while discussing the results obtained in what concerns the establishment of interference mechanisms in vivo and the environmental factors that could determine that. We also overview the molecular mechanisms by which lactobacilli species have been shown to inhibit pathophysiology of Candida, including the description of the genes and pathways determining their ability to thrive in the presence of each other. In a time where concerns are increasing with the emergence of antifungal resistance and the slow pace of discovery of new antifungals, a thorough understanding of the molecular mechanisms underneath the anti-Candida effect prompted by vaginal lactobacilli is of utmost importance to assure a knowledge-based design of what can be a new generation of pharmaceuticals, eventually focusing therapeutic targets other than the usual ones.

Contraceptive effects on the cervicovaginal microbiome: Recent evidence including randomized trials

BACKGROUND

Until recently, most data regarding the effects of non-barrier contraceptives on the mucosal microbiome have derived from observational studies, which are potentially biased due to behavioral confounders that may mask their true biological effects.

METHOD OF STUDY

This narrative review summarises recent evidence of the effect of contraceptives on the cervicovaginal microbiome, emphasising data obtained through randomized trials.

RESULTS

Good quality data describe that initiation of long-acting progestin-only contraceptives, including levonorgestrel (LNG)-implant and the injectables depot-medroxyprogesterone acetate (DMPA-IM) and norethisterone enanthate (NET-EN) do not alter the mucosal microbial environment. Likewise, no strong evidence exists that the use of oral contraceptive pills (OCPs) is associated with alterations of the vaginal microbiome or increased risk of bacterial sexually transmitted infections (STIs). Limited data on the effect of intravaginal rings (IVRs) on the mucosal environment exist and show conflicting effects on the vaginal microbiota. Copper intrauterine device (Cu-IUD) initiation has been associated with bacterial vaginosis (BV) acquisition, including in a randomized trial. LNG-IUDs may have similar affects but need to be evaluated further.

CONCLUSION

Different synthetic hormones have divergent effects on the microbiome and therefore novel hormonal methods need to be rigorously evaluated. Furthermore, the addition of antiretrovirals into multipurpose technologies may alter the effects of the hormonal component. There is thus a critical need to improve our understanding of the biological effects of contraceptive hormones and delivery methods with different pharmacokinetic and chemical properties on the mucosal microbiome in rigorous trials, to inform the development of novel contraceptives and improve individual family planning guidance.

Systems analysis reveals differential expression of endocervical genes in African women randomized to DMPA-IM, LNG implant or cu-IUD

Although effective contraceptives are crucial for preventing unintended pregnancies, evidence suggests that their use may perturb the female genital tract (FGT). A comparative analysis of the effects of the most common contraceptives on the FGT have not been evaluated in a randomized clinical trial setting. Here, we evaluated the effect of three long-acting contraceptive methods: depot medroxyprogesterone acetate(DMPA-IM), levonorgestrel(LNG) implant, and a copper intrauterine device (Cu-IUD), on the endocervical host transcriptome in 188 women from the Evidence for Contraceptive Options and HIV Outcomes Trial (ECHO) trial. Cu-IUD usage showed the most extensive transcriptomic changes, and was associated with inflammatory and anti-viral host responses. DMPA-IM usage was enriched for pathways associated with T cell responses. LNG implant had the mildest effect on endocervical gene expression, and was associated with growth factor signaling. These data provide a mechanistic basis for the diverse influence that varying contraceptives have on the FGT.

Assessment of Symptoms and Risk Factors as a Screening Tool of Bacterial Vaginosis Among Reproductive Age-Group Females in West Bengal, India

Background Bacterial vaginosis (BV) is a ubiquitous vaginal discomfort and has overlapping symptoms with other reproductive tract infections. The World Health Organization suggested a symptomatic approach for diagnosing BV with insufficient laboratory setup. However, due to symptom overlap, BV is often misled and ends up with injudicious drug application. Objective The study aims to identify the most relevant symptoms and behavioral risk factors associated with BV in tertiary healthcare settings in West Bengal, India. It also seeks to develop a scoring system based on clinical symptoms to screen for BV, especially when laboratory facilities are limited. Methodology The study is a retrospective case-control study involving 95 women of reproductive age. It employs both univariate and multivariate binary logistic regression models to identify risk factors and symptoms associated with BV. The study also compares these clinical symptoms with laboratory tests (Amsel's test) and attempts to create a scoring system for BV diagnosis. Key Findings Good menstrual hygiene and condom use were identified as key behavioral practices reducing the risk of BV. Four clinical symptoms, like malodor (P = 0.007), lower abdominal pain (P = 0.015), abnormal vaginal discharge (P = 0.071), and painful intercourse (P = 0.08), were identified as notable predictors. Based on these four symptoms, the scoring system showed a sensitivity of 88.2%, a specificity of 67.25%, and an overall accuracy of 74.7%. An additional diagnosis of vulvovaginal candidiasis (VVC) revealed that the odds of malodor (P= 0.006) and burning sensation (P= 0.011) increased significantly during co-infection.

Beyond fluconazole: A review of vulvovaginal candidiasis diagnosis and treatment

ABSTRACT

Vaginitis symptoms are among the most common reasons for patients to seek acute gynecological care. NPs who care for women and other patients with vaginas need to be up-to-date on diagnosis and treatment of vulvovaginal candidiasis (VVC) and recurrent VVC (RVVC). Two new antifungal medications for VVC are available. This article reviews vaginal physiology and provides an overview of VVC and RVVC pathophysiology, diagnosis, and treatment options.

Update on the Impact of Depot Medroxyprogesterone Acetate on Vaginal Mucosal Endpoints and Relevance to Sexually Transmitted Infections

PURPOSE OF REVIEW

The long-acting reversible intramuscularly-injected contraceptive depot medroxyprogesterone acetate (DMPA-IM) is widely used by cisgender women in Africa. Although DMPA-IM provides reliable contraception, potential effects on the female genital tract (FGT) mucosa have raised concern, including risk of HIV infection. This review summarises and compares evidence from observational cohort studies and the randomised Evidence for Contraceptive Options in HIV Outcomes (ECHO) Trial.

RECENT FINDINGS

Although previous observational studies found women using DMPA-IM had higher abundance of bacterial vaginosis (BV)-associated bacteria, increased inflammation, increased cervicovaginal HIV target cell density, and epithelial barrier damage, sub-studies of the ECHO Trial found no adverse changes in vaginal microbiome, inflammation, proteome, transcriptome, and risk of viral and bacterial STIs, other than an increase in Th17-like cells. Randomised data suggest that DMPA-IM use does not adversely change mucosal endpoints associated with acquisition of infections. These findings support the safe use of DMPA-IM in women at high risk of acquiring STIs, including HIV.

Influence of Hormonal Contraceptive Use and HIV on Cervicovaginal Cytokines and Microbiota in Malawi

Important questions remain on how hormonal contraceptives alter the local immune environment and the microbiota in the female genital tract and how such effects may impact susceptibility to HIV infection. We leveraged samples from a previously conducted clinical trial of Malawian women with (n = 73) and without (n = 24) HIV infection randomized to depot medroxyprogesterone acetate (DMPA) or the levonogestrel implant in equal numbers within each group and determined the effects of these hormonal contraceptives (HCs) on the vaginal immune milieu and the composition of the vaginal microbiota. Longitudinal data for soluble immune mediators, measured by multiplex bead arrays and enzyme-linked immunosorbent assays (ELISAs), and vaginal microbiota, assessed by 16S rRNA gene amplicon, were collected prior to and over a period of 180 days post-HC initiation. DMPA and levonogestrel had only minimal effects on the vaginal immune milieu and microbiota. In women with HIV, with the caveat of a small sample size, there was an association between the median log₁₀ change in the interleukin-12 (IL-12)/IL-10 ratio in vaginal fluid at day 180 post-HC compared to baseline when these women were classified as having a community state type (CST) IV vaginal microbiota and were randomized to DMPA. Long-lasting alterations in soluble immune markers or shifts in microbiota composition were not observed. Furthermore, women with HIV did not exhibit increased viral shedding in the genital tract after HC initiation. Consistent with the results of the ECHO (Evidence for Contraceptive Options and HIV Outcomes) trial, our data imply that the progestin-based HC DMPA and levonorgestrel are associated with minimal risk for women with HIV. (This study has been registered at ClinicalTrials.gov under registration no. NCT02103660). IMPORTANCE The results of the Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial, the first large randomized controlled clinical trial comparing the HIV acquisition risk of women receiving DMPA, the levonorgestrel (LNG) implant, or the copper intrauterine device (IUD), did not reveal an increased risk of HIV acquisition for women on any of these three contraceptives. Our study results confirm that the two different progestin-based hormonal contraceptives DMPA and levonogestrel will not increase the risk for HIV infection. Furthermore, DMPA and levonogestrel have only minimal effects on the immune milieu and the microbiota in the vaginal tract, attesting to the safety of these hormonal contraceptives.

An Integrative Review of the Relationship Between Intrauterine Devices and Bacterial Vaginosis

OBJECTIVE

To examine the relationship between intrauterine devices (IUDs) and bacterial vaginosis (BV) through an integrative review of the current literature.

DATA SOURCES

CINAHL, MEDLINE, Health Source, Evidence-Based Medicine's Cochrane Central Registry of Controlled Trials, Embase, and Web of Science databases were searched.

STUDY SELECTION

Cross-sectional, case-control, cohort, quasi-experimental, and randomized controlled trials examining copper (Cu-IUD) and levonorgestrel (LNG-IUD) use in reproductive- age users with BV occurrence confirmed with Amsel's criteria or Nugent scoring were included. Articles included were published in the past 10 years.

DATA EXTRACTION

Fifteen studies met criteria, after an initial search identified 1,140 potential titles, and two reviewers assessed 62 full-text articles for inclusion.

DATA SYNTHESIS

Data were categorized into three groups: retrospective descriptive cross-sectional studies identifying point prevalence of BV among IUD users; prospective analytic studies examining BV incidence and prevalence among Cu-IUD users; and prospective analytic studies examining BV incidence and prevalence among LNG-IUD users.

CONCLUSION

Synthesis and comparison of studies were difficult because of disparate study designs, sample sizes, comparator groups, and inclusion criteria for individual studies. Synthesis of data from cross-sectional studies showed that all IUD users combined may have an increased point prevalence of BV compared with non-IUD users. These studies did not delineate LNG-IUDs from Cu-IUDs. Findings from cohort and experimental studies suggest a possible increase in BV occurrence among Cu-IUD users. Evidence is lacking to show an association between LNG-IUD use and BV.

Copper intrauterine device increases vaginal concentrations of inflammatory anaerobes and depletes lactobacilli compared to hormonal options in a randomized trial

Effective contraceptives are a global health imperative for reproductive-aged women. However, there remains a lack of rigorous data regarding the effects of contraceptive options on vaginal bacteria and inflammation. Among 218 women enrolled into a substudy of the ECHO Trial (NCT02550067), we evaluate the effect of injectable intramuscular depot medroxyprogesterone acetate (DMPA-IM), levonorgestrel implant (LNG), and a copper intrauterine device (Cu-IUD) on the vaginal environment after one and six consecutive months of use, using 16S rRNA gene sequencing and multiplex cytokine assays. Primary endpoints include incident BV occurrence, bacterial diversity, and bacterial and cytokine concentrations. Secondary endpoints are bacterial and cytokine concentrations associated with later HIV seroconversion. Participants randomized to Cu-IUD exhibit elevated bacterial diversity, increased cytokine concentrations, and decreased relative abundance of lactobacilli after one and six months of use, relative to enrollment and other contraceptive options. Total bacterial loads of women using Cu-IUD increase 5.5 fold after six months, predominantly driven by increases in the concentrations of several inflammatory anaerobes. Furthermore, growth of L. crispatus (MV-1A-US) is inhibited by Cu2+ ions below biologically relevant concentrations, in vitro. Our work illustrates deleterious effects on the vaginal environment induced by Cu-IUD initiation, which may adversely impact sexual and reproductive health.

Lactobacillus-dominance and rapid stabilization of vaginal microbiota in combined oral contraceptive pill users examined through a longitudinal cohort study with frequent vaginal sampling over two years

BACKGROUND

Bacterial vaginosis (BV), a condition in which vaginal Lactobacillus spp. are in low abundance, is associated with vulvovaginal symptoms, obstetric outcomes and urogenital infections. Recurrent BV is difficult to manage, and emerging data indicate a reduced risk of BV with the use of hormonal contraception (HC). Despite widespread use, little longitudinal data is available on whether, and in what timeframe, combined oral contraceptive pills (COCs) may act to affect vaginal microbiota stability and Lactobacillus dominance.

METHODS

We compared the vaginal microbiota of reproductive-age cisgender women during intervals on combined estrogen and progestin COCs with non-use intervals in a 2-year observational study. Vaginal microbiota were characterized by 16S rRNA gene amplicon sequencing.

FINDINGS

COC users were more likely to have Lactobacillus-dominated microbiota and more stable microbiota over time. Stability increased and then plateaued four weeks after COC initiation. The associations between COCs and Lactobacillus spp. dominance, and microbiota stability, were statistically significant for White, but not African American women; however sample size was limited for African American participants. Findings were similar for other forms of HC and when excluding samples collected during menses.

INTERPRETATION

Our study provides a methodologic framework to evaluate observational longitudinal microbiota data with exposure crossovers. We found COCs are associated with vaginal microbiota stability and a Lactobacillus-dominated state. COCs appear to impact stability within a month of initiation. Our findings have clinical implications for how soon benefits can be expected in (at least White) patients initiating COCs, and support the need for larger prospective trials to verify our results in ethnically diverse populations.

FUNDING

R01-AI089878.

Hormonal contraceptive use and the risk of sexually transmitted infections: a systematic review and meta-analysis

There are 150 million women worldwide using combined or progestogen-only hormonal contraceptive methods who may be at risk of sexually transmitted infections (STIs). Previous systematic reviews that have sought to establish whether there is an aetiological association between hormonal contraceptive methods/use and STIs have been limited in their methods and have mixed findings. We sought to update these reviews using appropriate control groups. We undertook a systematic review following the PRISMA guidelines and meta-analysis to examine the association between the use of all hormonal contraceptive methods and the acquisition of STIs (Neisseria gonorrhoeae, syphilis/Treponema pallidum, Chlamydia trachomatis, herpes simplex virus, and Trichomonas vaginalis) and/or bacterial vaginosis in literature published between 2005 and 2020. We analysed the effect of hormonal contraceptive methods/use separately on the prevalence, incidence and recurrence of STIs. A total of 37 studies were included in this review that reported 61 associations, in which 27 prevalence, eight incidence and two recurrence studies provided 43, 16, and two associations, respectively. We observed a positive association between hormonal contraceptive methods/use and the risk of chlamydia and herpes but a negative association for trichomoniasis and vaginosis. A negative but statistically insignificant association was observed between hormonal contraceptive methods/use and gonorrhoea. Hormonal contraceptive methods/use influences a woman's risk of STIs/ bacterial vaginosis, but the risk may differ depending on the type of STI. These findings should be contextualized carefully, particularly when formulating practice guidelines and policy, as the effects of hormonal contraceptive methods/use on the risk of STIs varied in direction when analysed separately by STI.

Evaluating the impact of three progestin-based hormonal contraceptive methods on immunologic changes in the female genital tract and systemically (CHIME Study): a prospective cohort study protocol

BACKGROUND

Gonadal hormones can modify immune function, which may impact susceptibility to infectious diseases, including Human Immunodeficiency Virus (HIV). There is limited knowledge about how hormonal contraceptives (HC) influence the immune response during the course of use. The CHIME study aims to evaluate the effect of long-acting progestin-based hormonal contraceptives (depot medroxyprogesterone acetate, etonogestrel implant, and levonorgestrel intrauterine device) on immunologic changes in the female genital tract (FGT) and systemic compartment.

METHODS

CHIME is an observational cohort study where participants attend 2 visits prior to initiating the HC method of their choice, and then attend 6 visits over 12 months with biological sampling (vaginal swabs, cervicovaginal lavage, cytobrush and blood) for immunological, bacteriological, and virological analyses at each visit. Immune profiling will be evaluated by multi-color flow cytometry to determine how different T-cell subsets, in particular the CD4 T-cell subsets, change during the course of contraceptive use and whether they have different profiles in the FGT compared to the systemic compartment. The study aims are (1) to characterize the alterations in FGT and systemic immune profiles associated with three long-acting progestin-only HC and (2) to evaluate the vaginal microenvironment, determined by 16 s rRNA sequencing, as an individual-level risk factor and moderator of genital and systemic immune profile changes following exposure to three commonly used HC. Data collection started in March 2019 and is scheduled to be completed in October 2024.

DISCUSSION

The CHIME study aims to contribute to the body of research designed to evaluate the comparative impact of three long-acting progestin-only HC on innate and adaptive immune functions to understand how immunologic effects alter STI and HIV susceptibility.

Microbial and human transcriptome in vaginal fluid at midgestation: Association with spontaneous preterm delivery

BACKGROUND

Intrauterine infection and inflammation caused by microbial transfer from the vagina are believed to be important factors causing spontaneous preterm delivery (PTD). Multiple studies have examined the relationship between the cervicovaginal microbiome and spontaneous PTD with divergent results. Most studies have applied a DNA-based assessment, providing information on the microbial composition but not transcriptional activity. A transcriptomic approach was applied to investigate differences in the active vaginal microbiome and human transcriptome at midgestation between women delivering spontaneously preterm versus those delivering at term.

METHODS

Vaginal swabs were collected in women with a singleton pregnancy at 18 + 0 to 20 + 6 gestational weeks. For each case of spontaneous PTD (delivery <37 + 0 weeks) two term controls were randomized (39 + 0 to 40 + 6 weeks). Vaginal specimens were subject to sequencing of both human and microbial RNA. Microbial reads were taxonomically classified using Kraken2 and RefSeq as a reference. Statistical analyses were performed using DESeq2. GSEA and HUMAnN3 were used for pathway analyses.

RESULTS

We found 17 human genes to be differentially expressed (false discovery rate, FDR < 0.05) in the preterm group (n = 48) compared to the term group (n = 96). Gene expression of kallikrein-2 (KLK2), KLK3 and four isoforms of metallothioneins 1 (MT1s) was higher in the preterm group (FDR < 0.05). We found 11 individual bacterial species to be differentially expressed (FDR < 0.05), most with a low occurrence. No statistically significant differences in bacterial load, diversity or microbial community state types were found between the groups.

CONCLUSIONS

In our mainly white population, primarily bacterial species of low occurrence were differentially expressed at midgestation in women who delivered preterm versus at term. However, the expression of specific human transcripts including KLK2, KLK3 and several isoforms of MT1s was higher in preterm cases. This is of interest, because these genes may be involved in critical inflammatory pathways associated with spontaneous PTD.

Compliance with the Updated BASHH Recurrent Vulvovaginal Candidiasis Guidelines Improves Patient Outcomes

Recurrent vulvovaginal candidiasis (RVVC) is a debilitating, chronic condition that affects over 138 million (6%) women of reproductive age annually. We performed a retrospective audit of RVVC referrals to our tertiary care Candida clinic to evaluate the impact of the significantly updated British Association of Sexual Health and HIV (BASHH) 2019 vulvovaginal candidiasis guidelines on patient outcomes, the principles of which were implemented at our centre at the onset of the guideline revision process in 2017. A total of 78 women referred with suspected RVVC in 2017–2020 were included. Their mean symptom duration prior to referral was 6.7 years. RVVC was the definitive diagnosis in 73% of cases. In the 27% of patients without RVVC, the most common diagnoses were acute VVC (29%), vulval eczema (14%), dry skin (14%) and vulvodynia (10%). Of those with RVVC, 60% were diagnosed with an additional diagnosis, most commonly vulval eczema or vulvodynia. Only 12% of women had been counselled on appropriate vulval skin care, the mainstay of RVVC management. Long-term antifungal suppression was initiated in 68% of women. Azole-resistant Candida, for which there is no licensed treatment available in the UK, was identified in 23% of women with RVVC. In the follow-up, 82% of patients reported good control of symptoms using antifungal suppression therapy and recommended skin care, 16% had partial symptom control with some “flare-ups” responding to treatment, none reported poor control and for 2% this information was not available. RVVC-related morbidity can be reduced by following the principles outlined in the BASHH guidelines.

Genital inflammatory status and the innate immune response to contraceptive initiation

PROBLEM

Data on the effects of contraceptives on female genital tract (FGT) immune mediators are inconsistent, possibly in part due to pre-existing conditions that influence immune mediator changes in response to contraceptive initiation.

METHODS

This study included 161 South African women randomised to injectable depot medroxyprogesterone acetate (DMPA-IM), copper intrauterine device (IUD), or levonorgestrel (LNG) implant in the Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial. We measured thirteen cytokines and antimicrobial peptides previously associated with HIV acquisition in vaginal swabs using Luminex and ELISA, before, and at 1 and 3 months after contraceptive initiation. Women were grouped according to an overall baseline inflammatory profile. We evaluated modification of the relationships between contraceptives and immune mediators by baseline inflammation, demographic, and clinical factors.

RESULTS

Overall, LNG implant and copper IUD initiation were associated with increases in inflammatory cytokines, while no changes were observed following DMPA-IM initiation. However, when stratifying by baseline inflammatory profile, women with low baseline inflammation in all groups experienced significant increases in inflammatory cytokines, while those with a high baseline inflammatory profile experienced no change or decreases in inflammatory cytokines.

CONCLUSION

We conclude that pre-contraceptive initiation immune profile modifies the effect of contraceptives on the FGT innate immune response.

Association between Cervical Microbiota and HPV: Could This Be the Key to Complete Cervical Cancer Eradication?

Simple Summary

The microbiota can modulate immune responses and modify the physiology of the human organism, thereby increasing infective risks and a neoplastic predisposition. In this review, we focus on the composition of the cervical microbiota, to identify the risk of developing Cervical Intraepithelial Neoplasia and better understand the interaction between cervico-vaginal microbiota and human papillomavirus as a means of promoting the identification of new therapeutic strategies. In fact, no therapy for HPV is yet available. A better understanding of the cervical micro-environment could be a key element allowing complete viral clearance to be achieved in largely affected populations.

Abstract

The heterogeneity of the cervico-vaginal microbiota can be appreciated in various conditions, both pathological and non-pathological, and can vary according to biological and environmental factors. Attempts are still in course to define the interaction and role of the various factors that constitute this community of commensals in immune protection, inflammatory processes, and the onset of precancerous lesions of the cervical epithelium. Despite the many studies on the relationship between microbiota, immunity, and HPV-related cervical tumors, further aspects still need to be probed. In this review article, we will examine the principal characteristics of microorganisms commonly found in cervico-vaginal specimens (i) the factors that notoriously condition the diversity and composition of microbiota, (ii) the role that some families of organisms may play in the onset of HPV-dysplastic lesions and in neoplastic progression, and (iii) possible diagnostic-therapeutic approaches.

Systems Analysis Reveals Contraceptive-Induced Alteration of Cervicovaginal Gene Expression in a Randomized Trial

Hormonal contraceptives (HCs) are vital in managing the reproductive health of women. However, HC usage has been linked to perturbations in cervicovaginal immunity and increased risk of sexually transmitted infections. Here, we evaluated the impact of three HCs on the cervicovaginal environment using high-throughput transcriptomics. From 2015 to 2017, 130 adolescent females aged 15-19 years were enrolled into a substudy of UChoose, a single-site, open-label randomized, crossover trial (NCT02404038) and randomized to injectable norethisterone-enanthate (Net-En), combined oral contraceptives (COC), or etonorgesterol/ethinyl-estradiol-combined contraceptive vaginal ring (CCVR). Cervicovaginal samples were collected after 16 weeks of randomized HC use and analyzed by RNA-Seq, 16S rRNA gene sequencing, and Luminex analysis. Participants in the CCVR arm had a significant elevation of transcriptional networks driven by IL-6, IL-1, and NFKB, and lower expression of genes supporting epithelial barrier integrity. An integrated multivariate analysis demonstrated that networks of microbial dysbiosis and inflammation best discriminated the CCVR arm from the other contraceptive groups, while genes involved in epithelial cell differentiation were predictive of the Net-En and COC arms. Collectively, these data from a randomized trial represent the most comprehensive "omics" analyses of the cervicovaginal response to HCs and provide important mechanistic guidelines for the provision of HCs in sub-Saharan Africa.

The Effect of Exogenous Sex Steroids on the Vaginal Microbiota: A Systematic Review

Background

Exogenous sex steroids within hormonal contraception and menopausal hormone therapy (MHT) have been used for family planning and management of menopausal symptoms, without consideration of their effects on the vaginal microbiota. This is largely because their use predates our understanding of the importance of the vaginal microbiome on human health. We conducted a systematic review (PROSPERO: CRD42018107730) to determine the influence of exogenous sex steroids, stratified by oestrogen-containing or progestin-only types of contraception, and MHT on the vaginal microbiome, as measured by molecular methods.

Methods

Embase, PubMed and Medline were searched for relevant literature published through to December 1st 2020. Eligible studies reported on the effect of specific exogenous sex steroids on the vaginal microbiome using a molecular method. Data regarding the ‘positive’, ‘negative’ or ‘neutral’ effect of each type of contraceptive or MHT on the vaginal microbiome was extracted and summarised. A positive effect reflected sex steroid exposure that was associated with increased abundance of lactobacilli, a change to, or maintenance of, an optimal vaginal microbiota composition, or a decrease in bacterial diversity (specifically reflecting a low-diversity optimal microbiota state), relative to the control group. An exogenous sex steroid was designated as having a negative effect on the vaginal microbiome if it resulted in opposing effects (i.e. loss of lactobacilli, a non-optimal microbiota state). When no significant change was found, this was considered neutral/inconclusive.

Results

We identified 29 manuscripts reporting on the effect of exogenous sex steroids on the vaginal microbiome; 25 investigating hormonal contraceptives, and 4 investigating MHT. Oestrogen-containing contraception, particularly reflecting the combined oestrogen and progestin-containing contraceptive pill, had a positive effect on the composition of the vaginal microbiota. Progestin-only contraception, particularly reflecting depo-medroxyprogesterone acetate, had mixed effects on the microbiota. Among post-menopausal women using MHT, exogenous oestrogen applied topically was associated with increased prevalence of lactobacilli.

Conclusion

Our findings suggest that oestrogen-containing compounds may promote an optimal vaginal microbiota, which could have clinical applications. The impact of progestin-only contraceptives on the vaginal microbiota is less clear; more data is needed to determine how progestin-only contraceptives contribute to adverse reproductive and sexual health outcomes.

Antigen Presenting Cells Link the Female Genital Tract Microbiome to Mucosal Inflammation, With Hormonal Contraception as an Additional Modulator of Inflammatory Signatures

The microbiome of the female genital tract (FGT) is closely linked to reproductive health outcomes. Diverse, anaerobe-dominated communities with low Lactobacillus abundance are associated with a number of adverse reproductive outcomes, such as preterm birth, cervical dysplasia, and sexually transmitted infections (STIs), including HIV. Vaginal dysbiosis is associated with local mucosal inflammation, which likely serves as a biological mediator of poor reproductive outcomes. Yet the precise mechanisms of this FGT inflammation remain unclear. Studies in humans have been complicated by confounding demographic, behavioral, and clinical variables. Specifically, hormonal contraception is associated both with changes in the vaginal microbiome and with mucosal inflammation. In this study, we examined the transcriptional landscape of cervical cell populations in a cohort of South African women with differing vaginal microbial community types. We also investigate effects of reproductive hormones on the transcriptional profiles of cervical cells, focusing on the contraceptive depot medroxyprogesterone acetate (DMPA), the most common form of contraception in sub-Saharan Africa. We found that antigen presenting cells (APCs) are key mediators of microbiome associated FGT inflammation. We also found that DMPA is associated with significant transcriptional changes across multiple cell lineages, with some shared and some distinct pathways compared to the inflammatory signature seen with dysbiosis. These results highlight the importance of an integrated, systems-level approach to understanding host-microbe interactions, with an appreciation for important variables, such as reproductive hormones, in the complex system of the FGT mucosa.

Lactobacillus crispatus thrives in pregnancy hormonal milieu in a Nigerian patient cohort

Steroid hormones are one of the presumed modulators of Lactobacillus abundance in the vaginal epithelium. We set out to characterize the vaginal microbiome (VMB) and also provide an in-depth understanding of the relative contribution of estradiol (E2) and progesterone (P1) in shaping the vaginal microbiome of Nigerian women (n = 38) who experienced both uncomplicated term delivery and preterm delivery using samples longitudinally collected during pregnancy (17–21, 27–31, 36–41 weeks gestation) and 6 weeks postpartum. Vaginal swabs and blood samples were aseptically collected. Vaginal swabs were used for microbiome assessment using 16S ribosomal RNA (rRNA) gene sequencing. Blood samples were used for hormonal measurement using a competitive-based enzyme-linked immunosorbent assay (ELISA). Across several maternal covariates, maternal age, pregnancy status and delivery mode were not significantly associated with the vaginal microbiota whereas maternal E2 level (p_E2 = 0.006, Omnibus), and P1 level (p_P1 = 0.001, Omnibus) were significantly associated with the vaginal microbiome. E2 and P1 concentrations increased throughout pregnancy commensurately with increasing proportions of L. crispatus (p_E2 = 0.036, p_P1 = 0.034, Linear Mixed Model). An increasing trend of α-diversity was also observed as pregnancy progressed (p_{observed ASV} = 0.006, LMM). A compositional microbiome shift from Lactobacillus profile to non-Lactobacillus profile was observed in most postnatal women (p_{CST IV} < 0.001, LMM). Analysis of our data shows a species-specific link between pregnancy steroid hormone concentration and L. crispatus abundance.

Influence of Intramuscular Depot Medroxyprogesterone Acetate Initiation on Vaginal Microbiota in the Postpartum Period

BACKGROUND

The vaginal microbiome plays a key role in women's reproductive health. Use of exogenous hormones, such as intramuscular depot medroxyprogesterone acetate (DMPA-IM), may alter the composition of vaginal bacterial community.

METHODS

Vaginal swab samples were collected from postpartum Kenyan women initiating DMPA-IM or nonhormonal contraception (non-HC). Bacterial vaginosis was assessed by Nugent score (Nugent-BV) and bacterial community composition was evaluated using broad-range 16S ribosomal RNA gene polymerase chain reaction with high-throughput sequencing. Changes in Nugent score, alpha diversity (Shannon diversity index), and total bacterial load between contraceptive groups from enrollment to 3 months after initiation were estimated using multivariable linear mixed effects regression.

RESULTS

Among 54 human immunodeficiency virus-negative women, 33 choosing DMPA-IM and 21 choosing non-HC, Nugent-BV was more common among DMPA-IM users at enrollment. At follow-up, Nugent score had decreased significantly among DMPA-IM users (change, -1.89; 95% confidence interval [CI], -3.53 to -.25; P = .02) while alpha diversity remained stable (0.03; -.24 to .30; P = .83). Conversely, Nugent score remained relatively stable among non-HC users (change, -0.73; 95% CI, -2.18 to .73; P = .33) while alpha diversity decreased (-0.34; -.67 to -.001; P = .05). The total bacterial load decreased slightly in DMPA-IM users and increased slightly among non-HC users, resulting in a significant difference in change between the contraceptive groups (difference, -0.64 log10 gene copies per swab sample; 95% CI, -1.19 to -.08; P = .02). While significant changes in Nugent score and alpha diversity were observed within contraceptive groups, changes between groups were not significantly different.

CONCLUSIONS

Postpartum vaginal bacterial diversity did not change in DMPA-IM users despite a reduction in Nugent-BV, but it decreased significantly among women using non-HC. Choice of contraception may influence Lactobacillus recovery in postpartum women.

An updated review on the effects of depot medroxyprogesterone acetate on the mucosal biology of the female genital tract

Background

Access to safe, effective, and affordable contraception is important for women’s health and essential to mitigate maternal and fetal mortality rates. The progestin‐based contraceptive depot medroxyprogesterone acetate (DMPA) is a popular contraceptive choice with a low failure rate and convenient administration schedule.

Aim

In this review, we compiled observational data from human cohorts that examine how DMPA influences the mucosal biology of the female genital tract (FGT) that are essential in maintaining vaginal health, including resident immune cells, pro‐inflammatory cytokines, epithelial barrier function, and the vaginal microbiome

Materials and Methods

This review focused on the recent published literature published in 2019 and 2020.

Results

Recent longitudinal studies show that DMPA use associates with an immunosuppressive phenotype, increase in CD4+CCR5+ T cells, and alterations to growth factors. In agreement with previous meta‐analyses, DMPA use is associated with minimal effects of the composition of the vaginal microbiome. Cross‐sectional studies associate a more pro‐inflammatory relationship with DMPA, but these studies are confounded by inherent weaknesses of cross‐sectional studies, including differences in study group sizes, behaviors, and other variables that may affect genital inflammation.

Discussion & Conclusion

These recent results indicate that the interactions between DMPA and the vaginal mucosa are complex emphasizing the need for comprehensive longitudinal studies that take into consideration the measurement of multiple biological parameters.

The effect of different contraceptive methods on the vaginal microbiome

Introduction: Following a historical overview, the effect of different contraceptive methods on vaginal microbiome has been reviewed and summarized.Areas covered: Effects of combined hormonal contraceptives (oral or vaginal) and of progestin only (injectable and implantable), intrauterine devices/systems (copper- or levonorgestrel-releasing), on vaginal microbiome. In addition, mention is made of vaginal rings releasing antiviral drugs and lactic acid.Expert opinion: The vaginal microbiota (VM) is unique in that it is normally dominated by Lactobacillus species providing a degree of protection against infections; this however may vary, depending on the species and strains of Lactobacillus. Bacterial Vaginosis represents the most common dysbiosis of the VM and its prevalence can be influenced by use of contraception. Available evidence indicates that, under the influence of oral or systemically administered female sex hormones, there is apromotion of vaginal eubiosis, with aprevalence of ahealthy VM in which Lactobacilli predominate.

The Complex Link between the Female Genital Microbiota, Genital Infections, and Inflammation

The female genital tract microbiota is part of a complex ecosystem influenced by several physiological, genetic, and behavioral factors. It is uniquely linked to a woman's mucosal immunity and plays a critical role in the regulation of genital inflammation. A vaginal microbiota characterized by a high abundance of lactobacilli and low overall bacterial diversity is associated with lower inflammation. On the other hand, a more diverse microbiota is linked to high mucosal inflammation levels, a compromised genital epithelial barrier, and an increased risk of sexually transmitted infections and other conditions. Several bacterial taxa such as Gardnerella spp., Prevotella spp., Sneathia spp., and Atopobium spp. are well known to have adverse effects; however, the definitive cause of this microbial dysbiosis is yet to be fully elucidated. The aim of this review is to discuss the multiple ways in which the microbiota influences the overall genital inflammatory milieu and to explore the causes and consequences of this inflammatory response. While there is abundant evidence linking a diverse genital microbiota to elevated inflammation, understanding the risk factors and mechanisms through which it affects genital health is essential. A robust appreciation of these factors is important for identifying effective prevention and treatment strategies.

Vulvovaginal Candidosis (Excluding Mucocutaneous Candidosis): Guideline of the German (DGGG), Austrian (OEGGG) and Swiss (SGGG) Society of Gynecology and Obstetrics (S2k-Level, AWMF Registry Number 015/072, September 2020)

Aim The aim of this official guideline, published and coordinated by the German (DGGG), Austrian (OEGGG) and Swiss (SGGG) Societies of Gynecology and Obstetrics in collaboration with the DMykG, DDG and AGII societies, was to provide consensus-based recommendations obtained by evaluating the relevant literature for the diagnosis, treatment and management of women with vulvovaginal candidosis. Methods This S2k guideline represents the structured consensus of a representative panel of experts with a range of different professional backgrounds commissioned by the Guideline Committee of the above-mentioned societies. Recommendations This guideline gives recommendations for the diagnosis, management, counseling, prophylaxis and screening of vulvovaginal candidosis.

Association Between Vaginal Bacterial Microbiota and Vaginal Yeast Colonization

BACKGROUND

Vaginal yeast is frequently found with Lactobacillus-dominant microbiota. The relationship between vaginal yeast and other bacteria has not been well characterized.

METHODS

These analyses utilized data from the Preventing Vaginal Infections trial. Relative abundance of vaginal bacteria from 16S ribosomal ribonucleic acid gene amplicon sequencing and quantities of 10 vaginal bacteria using taxon-directed polymerase chain reaction assays were compared at visits with and without detection of yeast on microscopy, culture, or both.

RESULTS

Higher relative abundances of Megasphaera species type 1 (risk ratio [RR], 0.70; 95% confidence interval [CI], 0.52-0.95), Megasphaera species type 2 (RR, 0.81; 95% CI, 0.67-0.98), and Mageeibacillus indolicus (RR, 0.46; 95% CI, 0.25-0.83) were associated with lower risk of detecting yeast. In contrast, higher relative abundances of Bifidobacterium bifidum, Aerococcus christensenii, Lactobacillus mucosae, Streptococcus equinus/infantarius/lutentiensis, Prevotella bivia, Dialister propionicifaciens, and Lactobacillus crispatus/helveticus were associated with yeast detection. Taxon-directed assays confirmed that increasing quantities of both Megasphaera species and M indolicus were associated with lower risk of detecting yeast, whereas increasing quantities of L crispatus were associated with higher risk of detecting yeast.

CONCLUSIONS

Despite an analysis that examined associations between multiple vaginal bacteria and the presence of yeast, only a small number of vaginal bacteria were strongly and significantly associated with the presence or absence of yeast.

Guideline: Vulvovaginal candidosis (AWMF 015/072, level S2k)

Approximately 70-75% of women will have vulvovaginal candidosis (VVC) at least once in their lifetime. In premenopausal, pregnant, asymptomatic and healthy women and women with acute VVC, Candida albicans is the predominant species. The diagnosis of VVC should be based on clinical symptoms and microscopic detection of pseudohyphae. Symptoms alone do not allow reliable differentiation of the causes of vaginitis. In recurrent or complicated cases, diagnostics should involve fungal culture with species identification. Serological determination of antibody titres has no role in VVC. Before the induction of therapy, VVC should always be medically confirmed. Acute VVC can be treated with local imidazoles, polyenes or ciclopirox olamine, using vaginal tablets, ovules or creams. Triazoles can also be prescribed orally, together with antifungal creams, for the treatment of the vulva. Commonly available antimycotics are generally well tolerated, and the different regimens show similarly good results. Antiseptics are potentially effective but act against the physiological vaginal flora. Neither a woman with asymptomatic colonisation nor an asymptomatic sexual partner should be treated. Women with chronic recurrent Candida albicans vulvovaginitis should undergo dose-reducing maintenance therapy with oral triazoles. Unnecessary antimycotic therapies should always be avoided, and non-albicans vaginitis should be treated with alternative antifungal agents. In the last 6 weeks of pregnancy, women should receive antifungal treatment to reduce the risk of vertical transmission, oral thrush and diaper dermatitis of the newborn. Local treatment is preferred during pregnancy.

Predominance of Atopobium vaginae at Midtrimester: a Potential Indicator of Preterm Birth Risk in a Nigerian Cohort

Giving birth too soon accounts for half of all newborn deaths worldwide. Clinical symptoms alone are not sufficient to identify women at risk of giving birth too early, as such a pragmatic approach to reducing the incidence of preterm birth entails developing early strategies for intervention before it materializes.

Preterm birth (PTB) is the largest contributor to infant death in sub-Saharan Africa and globally. With a global estimate of 773,600, Nigeria has the third highest rate of PTB worldwide. There have been a number of microbiome profiling studies to identify vaginal microbiomes suggestive of preterm and healthy birth outcome. However, studies on the pregnancy vaginal microbiome in Africa are sparse with none performed in Nigeria. Moreover, few studies have considered the concurrent impact of steroid hormones and the vaginal microbiome on pregnancy outcome. We assessed two key determinants of pregnancy progression to gain a deeper understanding of the interactions between vaginal microbiome composition, steroid hormone concentrations, and pregnancy outcome. Vaginal swabs and blood samples were prospectively collected from healthy midtrimester pregnant women. Vaginal microbiome compositions were assessed by analysis of the V3-V5 region of 16S rRNA genes, and potential functional metabolic traits of identified vaginal microbiomes were imputed by PICRUSt (phylogenetic investigation of communities by reconstruction of unobserved states) analysis, while plasma estradiol (E2) and progesterone (P1) levels were quantified by the competitive enzyme-linked immunosorbent assay (ELISA). PTB vaginal samples were characterized by increased microbial richness, high diversity, and depletion of lactobacilli compared to term delivery samples. Women who delivered preterm were characterized by an Atopobium vaginae-dominated vagitype. High relative abundance of Atopobium vaginae at the midtrimester was highly predictive of PTB (area under the receiving operator characteristics [AUROC] of 0.983). There was a marked overlap in the range of plasma E2 and P1 values between term and PTB groups.

IMPORTANCE Giving birth too soon accounts for half of all newborn deaths worldwide. Clinical symptoms alone are not sufficient to identify women at risk of giving birth too early, as such a pragmatic approach to reducing the incidence of preterm birth entails developing early strategies for intervention before it materializes. In view of the role played by the vaginal microbiome and maternal steroid hormones in determining obstetric outcome, we assessed the vaginal microbiome composition and steroid hormone during pregnancy and examined their relationship in predicting preterm birth risk in Nigerian women. This study highlights a potential early-driver microbial marker for prediction of preterm birth risk and supports the notion that vaginal microbiome composition varies across populations. A knowledge of relevant preterm birth microbial markers specific to populations would enhance the development of personalized therapeutic interventions toward restoring a microbiome that optimizes reproductive health fitness, therefore reducing the incidence of preterm birth.

Sexually transmitted infections among women randomised to depot medroxyprogesterone acetate, a copper intrauterine device or a levonorgestrel implant

Objectives

Reproductive aged women are at risk of pregnancy and sexually transmitted infections (STI). Understanding drivers of STI acquisition, including any association with widely used contraceptives, could help us to reduce STI prevalence and comorbidities. We compared the risk of STI among women randomised to three contraceptive methods.

Methods

We conducted a secondary analysis to assess the risk of chlamydia and gonorrhoea in a clinical trial evaluating HIV risk among 7829 women aged 16–35 randomised to intramuscular depot medroxyprogesterone acetate (DMPA-IM), a copper intrauterine device (IUD) or a levonorgestrel (LNG) implant. We estimated chlamydia and gonorrhoea prevalences by contraceptive group and prevalence ratios (PR) using log-binomial regression.

Results

At baseline, chlamydia and gonorrhoea prevalences were 18% and 5%, respectively. Final visit chlamydia prevalence did not differ significantly between DMPA-IM and copper IUD groups or between copper IUD and LNG implant groups. The DMPA-IM group had significantly lower risk of chlamydia compared with the LNG implant group (PR 0.83, 95% CI 0.72 to 0.95). Final visit gonorrhoea prevalence differed significantly only between the DMPA-IM and the copper IUD groups (PR 0.67, 95% CI 0.52 to 0.87).

Conclusions

The findings suggest that chlamydia and gonorrhoea risk may vary with contraceptive method use. Further investigation is warranted to better understand the mechanisms of chlamydia and gonorrhoea susceptibility in the context of contraceptive use.

Hormonal contraception alters vaginal microbiota and cytokines in South African adolescents in a randomized trial

Young women in sub-Saharan Africa are disproportionally affected by HIV infection and unintended pregnancies. However, hormonal contraceptive (HC) use may influence HIV risk through changes in genital tract microbiota and inflammatory cytokines. To investigate this, 130 HIV negative adolescent females aged 15-19 years were enrolled into a substudy of UChoose, an open-label randomized crossover study (NCT02404038), comparing acceptability and contraceptive product preference as a proxy for HIV prevention delivery methods. Participants were randomized to injectable norethisterone enanthate (Net-En), combined oral contraceptives (COC) or etonorgesterol/ethinyl estradiol combined contraceptive vaginal ring (CCVR) for 16 weeks, then crossed over to another HC for 16 weeks. Cervicovaginal samples were collected at baseline, crossover and exit for characterization of the microbiota and measurement of cytokine levels; primary endpoints were cervical T cell activation, vaginal microbial diversity and cytokine concentrations. Adolescents randomized to COCs had lower vaginal microbial diversity and relative abundance of HIV risk-associated taxa compared to Net-En or CCVR. Cervicovaginal inflammatory cytokine concentrations were significantly higher in adolescents randomized to CCVR compared to COC and Net-En. This suggests that COC use may induce an optimal vaginal ecosystem by decreasing bacterial diversity and inflammatory taxa, while CCVR use is associated with genital inflammation.

Hormonal contraception and risk of STIs and bacterial vaginosis in South African adolescents: secondary analysis of a randomised trial

OBJECTIVES

Young women in sub-Saharan Africa are at high risk of STIs and unintended pregnancies, yet hormonal contraceptive (HC) use may affect STI risk. We compared the influence of three HCs on the incidence and prevalence of STIs and bacterial vaginosis (BV) in South African adolescents.

METHODS

One hundred and thirty adolescents between 15 and 19 years were randomised to the injectable norethisterone enanthate (Net-En), combined oral contraceptives (COC) (Triphasil or Nordette) or a combined contraceptive vaginal ring (CCVR; NuvaRing) for 16 weeks (clinicaltrials.gov/NCT02404038). Vaginal samples were collected at baseline and 16 weeks post contraceptive initiation for STI and BV testing.

RESULTS

In an intention-to-treat analysis, no significant differences in BV prevalence were found between study arms. The overall incidence of any STI at follow-up was high: 16.2% in the COC arm; 25.7% in the Net-En arm; and 37.1% in the CCVR arm. The incidence rate (IR) of any STI was similar between Net-En (IR 0.74 (95% CI 0.34 to 1.41)) and the oestrogen-containing contraceptives (IR 0.78 (95% CI 0.47 to 1.22)). A lower IR of Chlamydia trachomatis (incidence rate ratio (IRR) 0.68 (95% CI 0.19 to 1.99)) and Neisseria gonorrhoeae (IRR 0.25 (95% CI 0.01 to 1.35)) but a higher IR of Mycoplasma genitalium (IRR 16.0 (95% CI 2.96 to 400)), was observed in the Net-En arm compared with the oestrogen-containing contraceptives, although the overall incidence of M. genitalium was low (4.7%). In an exploratory analysis, the risk of any STI and N. gonorrhoeae was lower in the COC arm compared with CCVR. A per-protocol analysis yielded similar results.

CONCLUSION

Our results suggest that use of Net-En may be associated with increased risk of M. genitalium compared with oestrogen-containing contraceptives but not with overall STI risk. COC use may decrease STI risk relative to CCVR.

The vaginal microbiome of sub-Saharan African women: revealing important gaps in the era of next-generation sequencing

Accurate characterization of the vaginal microbiome remains a fundamental goal of the Human Microbiome project (HMP). For over a decade, this goal has been made possible deploying high-throughput next generation sequencing technologies (NGS), which indeed has revolutionized medical research and enabled large-scale genomic studies. The 16S rRNA marker-gene survey is the most commonly explored approach for vaginal microbial community studies. With this approach, prior studies have elucidated substantial variations in the vaginal microbiome of women from different ethnicities. This review provides a comprehensive account of studies that have deployed this approach to describe the vaginal microbiota of African women in health and disease. On the basis of published data, the few studies reported from the African population are mainly in non-pregnant post pubertal women and calls for more detailed studies in pregnant and postnatal cohorts. We provide insight on the use of more sophisticated cutting-edge technologies in characterizing the vaginal microbiome. These technologies offer high-resolution detection of vaginal microbiome variations and community functional capabilities, which can shed light into several discrepancies observed in the vaginal microbiota of African women in an African population versus women of African descent in the diaspora.

Daily Vaginal Microbiota Fluctuations Associated with Natural Hormonal Cycle, Contraceptives, Diet, and Exercise

The vaginal microbiome is a critical component of women’s sexual and reproductive health, with variations in microbial composition, particularly the loss of Lactobacillus species, being implicated in gynecologic and obstetric diseases. Given that the vaginal microbiome is so crucial, why do vaginal microbial profiles vary strikingly from person to person and even change over time within the same person? In the present study, which tracked the daily vaginal microbiomes of young healthy women through different lifestyles, we found that use of a locally released progestin contraceptive, a vegetarian diet, and intense exercise appear to lead to vaginal microbiome alterations and loss of Lactobacillus species. The impact of these vaginal microbiome changes on immediate and long-term health remain to be investigated.

The microorganisms of the vaginal tract are critical for vaginal and reproductive health. However, the regulation of these microorganisms is not well understood. Therefore, we investigated whether different factors regulate the vaginal microbiota of healthy college-aged women (n = 26) with high temporal resolution by collecting daily self-administered vaginal swabs and using 16S rRNA sequencing for bacterial identification. As expected, vaginal microbiota clustered into five predefined community state types. Vaginal microbial diversity, stability, and Lactobacillus abundances were associated with the menstrual cycle and hormonal contraceptive use. Vaginal microbial diversity, as measured using the Shannon index, increased during menses (P < 0.001), while Lactobacillus abundances decreased (P = 0.01). The covariance of these microbial measures with previously established estradiol levels suggests that estrogens can regulate vaginal microbiota. Moreover, the use of hormonal contraceptives may alter the temporal dynamics of the vaginal microbiota and decrease Lactobacillus abundances, depending on hormonal content and release method. Interestingly, intrasample diversity was greater in participants on a vegetarian diet (P = 0.004) and among participants who exercised more (P = 0.04). These findings indicate that ovarian hormones, diet, and exercise can regulate vaginal microbial composition and stability and may impact vaginal and reproductive health.

IMPORTANCE The vaginal microbiome is a critical component of women’s sexual and reproductive health, with variations in microbial composition, particularly the loss of Lactobacillus species, being implicated in gynecologic and obstetric diseases. Given that the vaginal microbiome is so crucial, why do vaginal microbial profiles vary strikingly from person to person and even change over time within the same person? In the present study, which tracked the daily vaginal microbiomes of young healthy women through different lifestyles, we found that use of a locally released progestin contraceptive, a vegetarian diet, and intense exercise appear to lead to vaginal microbiome alterations and loss of Lactobacillus species. The impact of these vaginal microbiome changes on immediate and long-term health remain to be investigated.

Hormonal Contraceptives and the Acquisition of Sexually Transmitted Infections: An Updated Systematic Review

BACKGROUND

Evidence suggests that some forms of hormonal contraception (HC) increase women's risk of non-human immunodeficiency virus sexually transmitted infections (STIs), yet evidence has not been reviewed since 2008. We conducted an updated systematic review to incorporate studies published between January 2009 and June 2017 to examine the relationship between HCs and incident or recurrent STIs.

METHODS

We searched PubMed and EMBASE to identify prospective studies comparing risk of Chlamydia trachomatis, Neisseria gonorrhoeae, human papillomavirus (HPV), herpes simplex virus type 2 (HSV-2), Treponema pallidum, or Trichomonas vaginalis, between women using HC versus nonhormonal methods or no methods. We summarize results by type of STI and HC and study quality using an adapted Newcastle-Ottawa Quality Assessment Scale.

RESULTS

Thirty articles met the inclusion criteria. Depo-medroxyprogesterone acetate (DMPA) reduces the risk of trichomoniasis (consistent evidence) and may increase the risk of HSV-2 (strong effect, few studies); inconclusive evidence exists for HPV, chlamydia, gonorrhea, and syphilis. Data on oral contraceptive pills (OCPs; generally not differentiated whether combined or progestin-only pills) suggest that use is associated with a reduced risk of trichomoniasis with inconclusive findings for HSV-2, HPV, chlamydia, gonorrhea, and syphilis. Very few studies included norethisterone enanthate (Net-En) injectable, implants or the levonorgestrel intrauterine device.

CONCLUSIONS

Depo-medroxyprogesterone acetate and OCPs reduce the risk of trichomoniasis and DMPA may increase the risk of HSV-2. However, the potential for confounding cannot be ruled out. Future studies should specify the type of injectable or OCP used to increase understanding of biological pathways; more research is needed on implants and hormonal intrauterine devices.

Pathobionts in the Vaginal Microbiota: Individual Participant Data Meta-Analysis of Three Sequencing Studies

Sequencing studies have shown that optimal vaginal microbiota (VMB) are lactobacilli-dominated and that anaerobes associated with bacterial vaginosis (BV-anaerobes) are commonly present. However, they overlooked a less prevalent but more pathogenic group of vaginal bacteria: the pathobionts that cause maternal and neonatal infections and pelvic inflammatory disease. We conducted an individual participant data meta-analysis of three VMB sequencing studies that included diverse groups of women in Rwanda, South Africa, and the Netherlands (2,044 samples from 1,163 women in total). We identified 40 pathobiont taxa but only six were non-minority taxa (at least 1% relative abundance in at least one sample) in all studies: Streptococcus (54% of pathobionts reads), Staphylococcus, Enterococcus, Escherichia/Shigella, Haemophilus, and Campylobacter. When all pathobionts were combined into one bacterial group, the VMB of 17% of women contained a relative abundance of at least 1%. We found a significant negative correlation between relative abundances (ρ = -0.9234), but not estimated concentrations (r = 0.0031), of lactobacilli and BV-anaerobes; and a significant positive correlation between estimated concentrations of pathobionts and BV-anaerobes (r = 0.1938) but not between pathobionts and lactobacilli (r = 0.0436; although lactobacilli declined non-significantly with increasing pathobionts proportions). VMB sequencing data were also classified into mutually exclusive VMB types. The overall mean bacterial load of the ≥20% pathobionts VMB type (5.85 log10 cells/μl) was similar to those of the three lactobacilli-dominated VMB types (means 5.13-5.83 log10 cells/μl) but lower than those of the four anaerobic dysbiosis VMB types (means 6.11-6.87 log10 cells/μl). These results suggest that pathobionts co-occur with both lactobacilli and BV-anaerobes and do not expand as much as BV-anaerobes do in a dysbiotic situation. Pathobionts detection/levels were increased in samples with a Nugent score of 4-6 in both studies that conducted Nugent-scoring. Having pathobionts was positively associated with young age, non-Dutch origin, hormonal contraceptive use, smoking, antibiotic use in the 14 days prior to sampling, HIV status, and the presence of sexually transmitted pathogens, in at least one but not all studies; inconsistently associated with sexual risk-taking and unusual vaginal discharge reporting; and not associated with vaginal yeasts detection by microscopy. We recommend that future VMB studies quantify common vaginal pathobiont genera.

Hormonal Contraception and Vaginal Infections Among Couples Who Are Human Immunodeficiency Virus Serodiscordant in Lusaka, Zambia

OBJECTIVE

To examine the relationship between hormonal contraception and vaginal infections with bacterial vaginosis, vaginal candidiasis, or trichomoniasis.

METHODS

Couples who were human immunodeficiency virus (HIV) serodiscordant in Zambia were enrolled in a longitudinal cohort study. From 1994 to 2002, both partners were seen quarterly and received physical exams including genital examinations. Separate rates for three outcome infections of interest (bacterial vaginosis, vaginal candidiasis, and trichomoniasis) were calculated. Bivariate associations between baseline and time-varying covariates and outcome infections of interest were evaluated using unadjusted Anderson-Gill survival models. Adjusted hazard ratios (aHRs) were generated using multivariable Anderson-Gill survival models that included demographic and clinical factors associated with both hormonal contraceptive use and each infection of interest.

RESULTS

There were 1,558 cases of bacterial vaginosis, 1,529 cases of vaginal candidiasis, and 574 cases of trichomoniasis over 2,143 person-years of observation. Depot medroxyprogesterone acetate (DMPA) users had significantly lower rates of trichomoniasis and bacterial vaginosis. In adjusted models, DMPA was protective for bacterial vaginosis (aHR=0.72; 95% CI 0.54-0.95), candidiasis (aHR 0.75, 95% CI 0.57-1.00) and trichomoniasis (aHR=0.43, 95% CI 0.25-0.74). Oral contraceptive pills were protective for candidiasis (aHR=0.79, 95% CI 0.65-0.97).

CONCLUSION

We confirm that DMPA use was associated with reduced rates of the three most common causes of vaginitis, and oral contraceptive pill use was associated with reduced rates of candidiasis among women in couples who were HIV discordant.

Changes in key vaginal bacteria among postpartum African women initiating intramuscular depot-medroxyprogesterone acetate

Background

The ECHO trial has relieved apprehension about intramuscular depot medroxyprogesterone acetate (DMPA-IM), however it is still important to understand how DMPA-IM affects the vaginal environment. We sought to describe how DMPA-IM initiation influences vaginal bacteria associated with HIV acquisition in postpartum women.

Methods

Vaginal swabs were collected for Nugent score determination and taxon-specific quantitative PCR of eight bacteria. Enrollment occurred at contraceptive initiation (DMPA-IM or non-hormonal contraception (non-HC)) and repeat vaginal swabs were collected after three months. Generalized estimating equations were used to estimate changes in Nugent score, total bacterial load, and taxa concentrations among contraceptive groups.

Results

Women who chose DMPA-IM (n = 33) were more likely to be married (97%vs.67%) and have resumed intercourse since delivery (52%vs.29%) compared to women who chose non-HC (n = 21). After three months, significant decreases in the concentrations of Sneathia species, Mycoplasma hominis, and Parvimonas species Type 1 were seen among non-HC users, however concentrations remained stable among DMPA-IM users; contraceptive method was associated with significantly different changes in M. hominis concentration between groups (p = 0.010).

Conclusions

Our findings suggest that postpartum use of DMPA-IM and non-HC may have differential impacts on the vaginal concentrations of some bacteria that have previously been associated with HIV acquisition.

Antepartum vaginal Candida colonization and the risk for obstetrical tears

Objective: Vaginal Candida colonization is very common during pregnancy. An association between Candida colonization and obstetrical tears has not yet been investigated. We investigated whether vaginal Candida colonization during pregnancy is associated with an increased risk for obstetrical tears.Study design: A prospective cohort study was undertaken between the years 2014-2016, comparing pregnancy and delivery characteristics of women with and without Candida colonization during pregnancy. Clinical characteristics of Candida positive women and those with normal vaginal flora were collected. To test the statistical significance of the categorical variables, the chi-square test or Fisher's exact test were used, where appropriate. For continuous variables, the Student's t-test was used.Results: During the study period, 102 women with vaginal Candida during pregnancy (of whom 70% had Candida albicans species) and 102 controls with normal vaginal flora were included in the analysis. No significant differences were observed between Candida positive women and those with normal vaginal flora. Pregnancy and delivery outcomes were comparable and no increased risk of obstetrical tears was found in the Candida group.Conclusions: Vaginal colonization with Candida species during pregnancy was not found to be associated with an increased risk of obstetrical tears.

Human papillomavirus infection and cervical dysplasia in HIV-positive women: potential role of the vaginal microbiota

OBJECTIVES

To assess the associations between microbiological markers of vaginal dysbiosis and incident/cleared/type-swap/persistent high-risk human papillomavirus (hrHPV) infection; and incident/cured/cleared/persistent high-grade cervical intraepithelial neoplasia (CIN2+) while controlling for persistent hrHPV infection.

DESIGN

Two nested case-control studies (N = 304 and 236) within a prospective cohort of HIV-positive women in Johannesburg, South Africa.

METHODS

Participants were examined for hrHPV type (INNO-LiPA), cervical dysplasia (histology), and vaginal microbiota (VMB) composition (V3-V4 Illumina HiSeq 2x300 bp) at baseline and endline, a median of 16 months later.

RESULTS

Women with incident hrHPV compared to those who remained hrHPV-negative were less likely to have an optimal Lactobacillus crispatus or jensenii-dominated VMB type at end-line [relative risk ratio (RRR) 0.125, P = 0.019], but not at baseline. Having different hrHPV types at both visits was associated with multiple anaerobic dysbiosis markers at baseline (e.g. increased bacterial vaginosis-associated anaerobes relative abundance: RRR 3.246, P = 0.026). Compared to women without CIN2+, but with hrHPV at both visits, women with incident CIN2+ had increased Simpson diversity (RRR 7.352, P = 0.028) and nonsignificant trends in other anaerobic dysbiosis markers at end-line but not baseline. These associations persisted after controlling for age, hormonal contraception, and CD4 cell count. Current hormonal contraceptive use (predominantly progestin-only injectables) was associated with increased CIN2+ risk over-and-above persistent hrHPV infection and independent of VMB composition.

CONCLUSIONS

hrHPV infection (and/or increased sexual risk-taking) may cause anaerobic vaginal dysbiosis, but a bidirectional relationship is also possible. In this population, dysbiosis did not increase CIN2+ risk, but CIN2+ increased dysbiosis risk. The CIN2+ risk associated with progestin-only injectable use requires further evaluation.

Fecal Microbiota Transplantation: A Potential Tool for Treatment of Human Female Reproductive Tract Diseases

The gastro-intestinal tract is an extensive organ involved in several activities, with a crucial role in immunity. Billions of commensal and transient microorganisms, known as the gut microbiota, and potential pathogens, which are constantly stimulating intestinal immunity, colonize the intestinal epithelial surface. The gut microbiota may be regarded as analogous to a solid organ with multiple different functions. In the last decade, many studies have demonstrated that intestinal bacteria can be a decisive factor in the health-disease balance of the intestine, and they can also be responsible for illnesses in other locations. For this reason, fecal microbiota transplantation (FMT) represents an important therapeutic option for Clostridium difficile infections and hold promise for different clinical conditions, such as multiple sclerosis, autism, obesity, and other systemic diseases. FMT consists of the infusion of a fecal suspension from a healthy donor to a recipient in order to restore gut flora alterations. Similar to the gut, the female reproductive tract is an example of a very complex biological ecosystem. Recent studies indicate a possible relationship between the gut and female tract microbiota, associating specific intestinal bacteria patterns with genital female diseases, such as polycystic ovary syndrome (PCOS), endometriosis and bacterial vaginosis (BV). FMT could represent a potential innovative treatment option in this field.

Medroxyprogesterone acetate alters the vaginal microbiota and microenvironment in women and increases susceptibility to HIV-1 in humanized mice

The hormonal contraceptive medroxyprogesterone acetate (MPA) is associated with increased risk of human immunodeficiency virus (HIV), via incompletely understood mechanisms. Increased diversity in the vaginal microbiota modulates genital inflammation and is associated with increased HIV-1 acquisition. However, the effect of MPA on diversity of the vaginal microbiota is relatively unknown. In a cohort of female Kenyan sex workers, negative for sexually transmitted infections (STIs), with Nugent scores <7 (N=58 of 370 screened), MPA correlated with significantly increased diversity of the vaginal microbiota as assessed by 16S rRNA gene sequencing. MPA was also significantly associated with decreased levels of estrogen in the plasma, and low vaginal glycogen and α-amylase, factors implicated in vaginal colonization by lactobacilli, bacteria that are believed to protect against STIs. In a humanized mouse model, MPA treatment was associated with low serum estrogen, low glycogen and enhanced HIV-1 susceptibility. The mechanism by which the MPA-mediated changes in the vaginal microbiota may contribute to HIV-1 susceptibility in humans appears to be independent of inflammatory cytokines and/or activated T cells. Altogether, these results suggest MPA-induced hypo-estrogenism may alter key metabolic components that are necessary for vaginal colonization by certain bacterial species including lactobacilli, and allow for greater bacterial diversity in the vaginal microbiota.

This article has an associated First Person interview with the first author of the paper.

Summary: MPA may increase susceptibility to HIV-1 in sex workers through the suppression of endogenous estrogen, reducing vaginal glycogen and α-amylase levels, which increases bacterial diversity, potentially reducing protective bacterial species such as lactobacilli.

Factors associated with the composition and diversity of the cervical microbiota of reproductive-age Black South African women: a retrospective cross-sectional study

Background

Lactobacillus spp. are common bacteria in the cervical and vaginal microbiota (CVM) and are thought to represent a “healthy” cervicovaginal state. Several studies have found an independent association between ethnicity/race and cervical and vaginal microbiota (CVM) composition. Women of sub-Saharan African descent appear to be significantly more likely to have non-Lactobacillus-dominated CVM compared to women of European descent. The factors contributing to these differences remain to be fully elucidated. The CVM of Black South African women and factors influencing their CVM remain understudied. In this study, we characterized the cervical microbiota of reproductive-age South African women and assessed the associations of these microbiota with participants’ metadata.

Methods

The cervical microbiota from cervical DNA of 62 reproductive-age women were profiled by Ion Torrent sequencing the V4 hypervariable region of the bacterial 16S ribosomal RNA (rRNA) gene and analyzed with the Quantitative Insights Into Microbial Ecology (QIIME), UPARSE, and metagenomeSeq tools. Associations between cervical microbiota and participants’ metadata were assessed using GraphPad Prism, R packages and an in-house script.

Results

The cervical microbiota clustered into three distinct community state types (CSTs): Lactobacillus iners-dominated cervical microbiota (CST I (38.7%, 24/62)), unclassified Lactobacillus-dominated cervical microbiota (CST II (4.8%, 3/62)), and diverse cervical microbiota (CST III (56.5%, 35/62)) with an array of heterogeneous bacteria, predominantly the bacterial vaginosis (BV)-associated Gardnerella, Prevotella, Sneathia, and Shuttleworthia. CST III was associated with BV (p = 0.001). Women in CST I were more likely to be on hormonal contraception, especially progestin-based, compared to women in CST III (odds ratio: 5.2 (95% CI [1.6–17.2]); p = 0.005). Women on hormonal contraception had a significantly lower alpha (Shannon indices: 0.9 (0.2–1.9) versus 2.3 (0.6–2.3); p = 0.025) and beta (permutational multivariate analysis of variance (PERMANOVA) pseudo-F statistic =4.31, p = 0.019) diversity compared to non-users. There was no significant difference in the alpha (Shannon indices: 1.0 (0.3–2.2) versus 1.9 (0.3–2.2); p = 0.483) and beta (PERMANOVA pseudo-F statistic = 0.89, p = 0.373) diversity in women with versus without human papillomavirus infection.

Conclusions

The majority of Black women in our study had non-Lactobacillus-dominated cervical microbiota. Additional studies are needed to examine whether such microbiota represent abnormal, intermediate or variant states of health. Lastly, the association of hormonal contraception with L. iners dominance requires further in-depth research to confirm this association, determine its biological mechanism and whether it has a beneficial effect on the cervicovaginal health.

Conventional oral and secondary high dose vaginal metronidazole therapy for recurrent bacterial vaginosis: clinical outcomes, impacts of sex and menses

Purpose

Oral metronidazole therapy is the standard of care for bacterial vaginosis (BV), yet it has alarming rates of recurrence and refractory responses among recurrent BV (RBV) patients. This study addresses whether high dose vaginal metronidazole therapy (HDM) is beneficial in RBV patients who fail after standard of care (SOC) therapy, whether diagnostic test scores proximal to the HDM predict clinical outcome, and whether menses, coitus, or race influences therapy outcome.

Patients and methods

A total of 90 patients with RBV were given SOC and tracked 74 for up to 9 months. Refractory or recurrent patients (57) with symptomatic BV were given HDM and followed for up to 8 months. Patients were evaluated by Amsel criteria, Nugent score, and a qPCR assay that assesses the Lactobacillus content.

Results

HDM achieved at least short-term remission in 68% of the patients who were refractory to or recurred after SOC and provided a 10-day increase in the mean duration of remission among patients who eventually recurred (p=0.027). Patients with prolonged dysbiosis (pH >5 or Amsel 4) before symptomatic recurrence were more likely to recur after subsequent HDM. Most recurrence happened within 10 days of menses, but sex in this cohort was not associated with clinical outcome. Mean diagnostic BV scores of African American patients in remission were inferior to scores of a small cohort of Caucasian patients in remission.

Conclusion

Encouraging results obtained with HDM justify a prospective, randomized study to determine if follow-up HDM is beneficial among a broader cohort of women failing conventional oral metronidazole therapy.

Vaginal microbiome profiles of pregnant women in Korea using a 16S metagenomics approach

PROBLEM

The stability and dominance of Lactobacillus spp. in vaginal fluid are important for reproductive health. However, the characterization of the vaginal microbiota of women with preterm labor (PTL) or preterm premature rupture of membranes (P-PROM), and its association with preterm birth (PTB) are poorly understood.

METHOD OF STUDY

We collected vaginal fluid from women at risk of PTB (n = 58) in five university hospitals in Korea. We performed a hierarchical clustering analysis and classification according to the Lactobacillus spp. and Lactobacillus abundance using Illumina MiSeq sequencing of 16S rRNA gene amplicons.

RESULTS

Women at risk for PTB caused by P-PROM had greater bacterial richness and diversity at the time of admission than those with PTL (P < 0.05). However, they were not significantly different between term and preterm samples. In the classification by Lactobacillus spp., the community commonly dominated by Bacteroides and Lactobacillus crispatus was found for the first time in pregnant women in Korea, and all women with this community delivered preterm. Intriguingly, women with an abundance of Weissella in a Bacteroides-dominant community delivered at term. Moreover, in the classification by Lactobacillus proportion, the abundances of Weissella and Rickettsiales were associated with term deliveries, but the abundances of Bacteroides and Escherichia-Shigella were associated with PTBs (P < 0.05).

CONCLUSION

This result suggests that Lactobacillus abundance-based classification of vaginal fluid may reveal the microbiome associated with PTB. Further studies are needed to investigate the mechanism underlying the link between the microbiome and PTB.

Recurrent vulvo-vaginal candidiasis in Abidjan (Côte d'Ivoire): Aetiology and associated factors

Recurrent vulvovaginal candidiasis (RVVC) is a major health problem for sexually active women because of its severe effect on their quality of life. A thorough knowledge of their epidemiology leads to their efficient management. Therefore, a cross-sectional study was conducted in 2014 in women with leucorrhoea associated or not with other clinical signs. Recurrence was based on the occurrence of at least four annual episodes of Candida vulvo-vaginitis. An individual interview based on a questionnaire was conducted to identify the socio-demographic parameters that could be associated with the RVVC. Vaginal samples were collected at the obstetrical gynaecology department of the University Hospital of Cocody and at the Pasteur Institute of Côte d'Ivoire. On each sample, a direct examination and culture on Sabouraud-chloramphenicol medium with or without actidione were performed. Yeast identification was performed using chromogenic media (CandiSelect^®4 [Bio-Rad]) and the study of sugar assimilation using the Auxacolor^® 2 gallery (Bio-Rad). A total of 400 patients were included. The average age was 29.2 years (SD=7.2 years). Of these, 94 had recurrent vulvovaginal candidiasis, with a prevalence of 23.5% (CI_95%: 19.49-28.02). Five species of the genus Candida have been identified: Candida albicans (59.6%), Candida glabrata (19.1%), Candida tropicalis (16%), Candida krusei (4.2%) and Candida inconspicua (1.1%). Some factors such as education level, history of sexually transmitted infection, type of underwear used, frequency of personal hygiene and type of product used for these hygiene have been associated with the occurrence of RVVCs. The occurrence of RVVCs is relatively high in our study population. Non-albicansCandida species occupy a significant place in this disease epidemiology. By addressing the factors associated with the occurrence and/or persistence of RVVCs, it will be possible to reduce their incidence in sexually active women.

Combined oral contraceptive pill-exposure alone does not reduce the risk of bacterial vaginosis recurrence in a pilot randomised controlled trial

We conducted a pilot open-label randomised controlled trial of combined (oestrogen-progesterone) oral contraceptive pill (COCP)-exposure aimed to examine its effect on BV-recurrence following first-line antibiotics compared to antibiotics alone. Ninety-five women with symptomatic BV were prescribed antibiotic therapy, randomised to COCP-exposure (intervention) or current non-hormonal contraceptive practices (control) and followed monthly for six-months or until BV-recurrence. Modified intention-to-treat methods requiring either ≥1 clinical (primary/Amsel-outcome) or ≥1 microbiological (secondary/Nugent-outcome) BV-recurrence assessment were applied to determine cumulative recurrence rates. Secondary Cox regression analyses assessed factors associated with recurrence in all women. 92/95 women randomised provided baseline requirements. BV-recurrence rates were similar in women randomised to the COCP (primary/Amsel-outcome: 10/100PY, 95%CI: 6,19/100PY) compared to controls (14/100PY, 95%CI: 9, 21/100PY, p = 0.471). In secondary analyses sex with the same pre-treatment regular sexual partner (RSP; Amsel: Adjusted Hazard Ratio [AHR] = 3.13, 95%CI: 1.41, 6.94, p = 0.005; Nugent: AHR = 2.97, 95%CI: 1.49, 5.83, p = 0.002) and BV-history (Amsel: AHR = 3.03, 95%CI: 1.14, 6.28; Nugent: AHR = 2.78, 95%CI: 1.22, 6.33) were associated with increased BV-recurrence. This pilot RCT of COCP-exposure did not improve BV cure but found sex with an RSP and BV-history were associated with recurrence, although impacted by sample size and attrition. These data indicate reinfection from an untreated RSP and persistence of BV-associated bacteria are integral to the pathogenesis of recurrence and may overwhelm potential beneficial effects of hormonal contraception on the vaginal microbiota.

Cervicovaginal microbiota, women's health, and reproductive outcomes

The human microbiome project has shown a remarkable diversity of microbial ecology within the human body. The vaginal microbiota is unique in that in many women it is most often dominated by Lactobacillus species. However, in some women it lacks Lactobacillus spp. and is comprised of a wide array of strict and facultative anaerobes, a state that broadly correlates with increased risk for infection, disease, and poor reproductive and obstetric outcomes. Interestingly, the level of protection against infection can also vary by species and strains of Lactobacillus, and some species although dominant are not always optimal. This factors into the risk of contracting sexually transmitted infections and possibly influences the occurrence of resultant adverse reproductive outcomes such as tubal factor infertility. The composition and function of the vaginal microbiota appear to play an important role in pregnancy and fertility treatment outcomes and future research in this field will shed further translational mechanistic understanding onto the interplay of the vaginal microbiota with women's health and reproduction.

Interplay among Vaginal Microbiome, Immune Response and Sexually Transmitted Viral Infections

The vaginal ecosystem is important for women's health and for a successful reproductive life, and an optimal host-microbial interaction is required for the maintenance of eubiosis. The vaginal microbiota is dominated by Lactobacillus species in the majority of women. Loss of Lactobacillus dominance promotes the colonization by anaerobic bacterial species with an increase in microbial diversity. Vaginal dysbiosis is a very frequent condition which affects the immune homeostasis, inducing a rupture in the epithelial barrier and favoring infection by sexually transmitted pathogens. In this review, we describe the known interactions among immune cells and microbial commensals which govern health or disease status. Particular attention is given to microbiota compositions which, through interplay with immune cells, facilitate the establishment of viral infections, such as Human Immunodeficiency Virus (HIV), Human Papilloma Virus (HPV), Herpes Simplex Virus 2 (HSV2).