Sarah Elizabeth Brown

Emerging evidence suggests a link between hyperosmolal vaginal lubricants and bacterial vaginosis. In 80 patients undergoing transvaginal ultrasound with a standardized lubricant, we observed a significant increase in Amsel-defined bacterial vaginosis 1 to 13 days after transvaginal ultrasound compared with baseline, likely driven by heightened amine odor (odds ratio, 5.88; 95% confidence interval, 1.22–28.23).

We evaluated how storing vaginal samples at room temperature in stabilising solutions versus immediate freezing affects 16S rRNA gene amplicon sequencing-based microbiota studies, aiming to simplify home and field collection. Methods Twenty participants self-collected six mid-vaginal swabs that were stored in two nucleic acid preservatives (three in modified Solution C2 (Qiagen) and three in Amies/RNALater (Sigma)) in January-February 2016. From each set, two were immediately frozen (−80°C) and one was shipped to the University of Idaho (Moscow, Idaho) with return shipping to the Institute for Genome Sciences (Baltimore, Maryland). Amplicon sequencing of the 16S rRNA gene was used to characterise the vaginal microbiota, VALENCIA was used to assign community state types (CSTs), and quantitative PCR (qPCR) of 16S rRNA genes was used to estimate bacterial abundance. Cohen’s Kappa statistic was used to assess within-participant agreement. Bayesian difference of means models assessed within-participant comparisons between shipped and immediately frozen samples. Results There were 115 samples available for analysis. Average duration of transit for shipped samples was 8 days (SD: 1.60, range: 6–11). Within-participant comparisons of CSTs between shipped and immediately frozen samples revealed complete concordance (kappa: 1.0) for both preservative solutions. No significant differences comparing shipped and immediately frozen samples were found with taxon-level comparisons or bacterial abundances based on pan-bacterial qPCR. Conclusions Short-term room temperature shipping of vaginal swabs placed in stabilising solutions did not affect vaginal microbiota composition. Home collection with mail-in of vaginal samples may be a reasonable approach for research and clinical purposes to assess the vaginal microbiota.

Bacterial vaginosis, characterized in part by low levels of vaginal Lactobacillus species, has been associated with pro-inflammatory cytokines which could fuel uterine fibroid development. However, prior work on the associations between uterine fibroids and vaginal bacteria is sparse. Most studies have focused on assessment of individual taxa in a single sample. To address research gaps, we sought to compare short, longitudinal profiles of the vaginal microbiota in uterine fibroid cases versus controls with assessment for hormonal contraceptives (HCs), a possible confounder associated with both protection from fibroid development and increases in Lactobacillus-dominated vaginal microbiota. This is a secondary analysis of 83 reproductive-age cisgender women who presented for transvaginal ultrasound (TVUS) and self-collected mid-vaginal swabs daily for 1–2 weeks before TVUS (Range: 5–16 days, n = 697 samples). Sonography reports detailed uterine fibroid characteristics (N = 21 cases). Vaginal microbiota was assessed by 16S rRNA gene amplicon sequencing and longitudinal microbiota profiles were categorized by hierarchical clustering. We compared longitudinal profiles of the vaginal microbiota among fibroid cases and controls with exact logistic regression. Common indications for TVUS included pelvic mass (34%) and pelvic pain (39%). Fibroid cases tended to be older and report Black race. Cases less often reported HCs versus controls (32% vs. 58%). A larger proportion of cases had low-Lactobacillus longitudinal profiles (48%) than controls (34%). In unadjusted analysis, L. iners-dominated and low-Lactobacillus profiles had higher odds of fibroid case status compared to other Lactobacillus-dominated profiles, however these results were not statistically significant. No association between vaginal microbiota and fibroids was observed after adjusting for race, HC and menstruation. Results were consistent when number of fibroids were considered. There was not a statistically significant association between longitudinal profiles of vaginal microbiota and uterine fibroids after adjustment for common confounders; however, the study was limited by small sample size.

We applaud the efforts of Palacios et al. ¹ in formulating and evaluating the safety and effectiveness of several water-based personal lubricants. The trial is thoughtfully designed, including washout and run-in periods between study phases, and the authors present a detailed analysis of changes in Female Sexual Function Index (FSFI) scores over a period of 4 weeks. Although the 4 lubricant products that Palacios et al. formulated for the trial were hyperosmolar, they were developed to comply with World Health Organization guidance on the maximum suggested pH (3.8-4.5) and osmolality (2 In the results section, the authors noted that none of the tested lubricants had a significant impact on vaginal pH or the composition of the vaginal microbiota after the 4-week usage period. However, we did not see any statistical analyses or numeric/visual data of these vaginal microenvironmental data, either in the main article, in supplementary files, or in an online repository. It is also unclear how the authors assessed the vaginal microbiota data. Key information was not included in the article, including vaginal swab storage conditions, DNA extraction protocol, 16S rRNA hypervariable region, sequencing platform, bioinformatic processing, taxonomic assignments, specific taxonomic outcomes, analytical sample size, and statistical analyses. ³ The authors did note that the microbiota and pH analyses were considered exploratory; still, without the information we have listed, we are unable to gauge the safety statements for the microbial outcomes of the study. Although vaginal pH certainly plays a role in overall female reproductive tract health, a lower pH does not always reflect an optimal Lactobacillus-dominated microbiota. ^{4, 5}

Up to 26% of urogenital Chlamydia trachomatis infections spontaneously resolve between detection and treatment. Mechanisms governing natural resolution are unknown. We examined whether bacterial vaginosis (BV) was associated with greater chlamydia persistence versus spontaneous clearance in a large, longitudinal study. Between 1999-2003, the Longitudinal Study of Vaginal Flora followed reproductive-age women quarterly for one year. Baseline chlamydia screening and treatment were initiated after ligase chain reaction testing became available mid-study, and unscreened endocervical samples were tested after study completion. Chlamydia clearance and persistence were defined between consecutive visits without chlamydia-active antibiotics (N = 320 persistence/N = 310 clearance). Associations between Nugent score (0-3, no BV; 4-10, intermediate/BV), Amsel-BV, and chlamydia persistence versus clearance were modeled with alternating and conditional logistic regression. 48% of chlamydia cases spontaneously cleared by the next visit (310/630). Nugent-Intermediate/BV was associated with higher odds of chlamydia persistence (aOR = 1.89, 95% CI:1.30-2.74), and the findings were similar for Amsel-BV (aOR 1.39, 95% CI:0.99-1.96). The association between Nugent-Intermediate/BV and chlamydia persistence was stronger in a within-participant analysis of 67 participants with both clearance/persistence intervals (aOR = 4.77, 95% CI:1.39-16.35). BV symptoms did not affect any results. BV is associated with greater chlamydia persistence. Optimizing the vaginal microbiome may promote chlamydia clearance.

Objectives: Observational studies demonstrate an association between vaginal douching and bacterial vaginosis (BV) characterised by Gram stain. We sought to describe the effect of a douching cessation intervention on the composition and structure of the vaginal microbiota and molecular-BV, a state defined by low levels of Lactobacillus spp evaluated by molecular tools.Methods: 33 women self-collected mid-vaginal swabs twice weekly (982 samples) during a douching observation phase (4 weeks) followed by a douching cessation phase (12 weeks) in a 2005 single crossover pilot study conducted in Baltimore, Maryland. Vaginal microbiota were characterised by 16S rRNA gene amplicon sequencing (V3-V4) and clustered into community state types (CSTs). Conditional logistic regression modelling allowed each participant to serve as their own control. Wilcoxon signed-rank tests were used to evaluate changes in microbiota between phases. Broad-range qPCR assays provided estimates of bacterial absolute abundance per swab in a subsample of seven participants before and after douching. A piecewise linear mixed effects model was used to assess rates of change in bacterial absolute abundance before and after douching.Results: There was no statistically significant change in the odds of molecular-BV versus Lactobacillus-dominated CSTs comparing the douching cessation interval to douching observation (adjusted OR 1.77, 95% CI 0.89 to 3.55). Removal of L. iners-dominated CST III from the outcome did not affect the results. There were no significant changes in the relative abundance of four Lactobacillus spp and no meaningful changes in other taxa investigated. There was no significant change in bacterial absolute abundance between a participant’s sample collected 3 days prior to and following douching (p=0.46).Conclusions: In this pilot study, douching cessation was not associated with major changes in vaginal microbiota. Douching cessation alone may not durably shift the vaginal microbiota and additional interventions may be needed to restore optimal vaginal microbiota among those who douche.

The human vaginal microbiota is a critical determinant of vaginal health. These communities live in close association with the vaginal epithelium and rely on host tissues for resources. Although often dominated by lactobacilli, the vaginal microbiota is also frequently composed of a collection of facultative and obligate anaerobes. The prevalence of these communities with a paucity of Lactobacillus species varies among women, and epidemiological studies have associated them with an increased risk of adverse health outcomes. The mechanisms that drive these associations have yet to be described in detail, with few studies establishing causative relationships. Here, we review our current understanding of the vaginal microbiota and its connection with host health. We centre our discussion around the biology of the vaginal microbiota when Lactobacillus species are dominant versus when they are not, including host factors that are implicated in shaping these microbial communities and the resulting adverse health outcomes. We discuss current approaches to modulate the vaginal microbiota, including probiotics and vaginal microbiome transplants, and argue that new model systems of the cervicovaginal environment that incorporate the vaginal microbiota are needed to progress from association to mechanism and this will prove invaluable for future research.

The outer layers of the vaginal epithelium (VE) are important because they accumulate glycogen which, under optimal conditions, Lactobacillus spp. consume to grow and acidify the vaginal microenvironment with lactic acid. We hypothesized that exposure to lubricant, for example in the conduct of a transvaginal ultrasound (TVUS), may contribute to the shedding of mature epithelial cells, exposing immature cells. Cervicovaginal fluid (CVF) was sampled at four time points by menstrual cup (Softdisc™) from 50 women referred for TVUS, during which a controlled volume of lubricant was applied to the TVUS wand. Samples were collected (1) immediately before TVUS and (2) 6–12 hours, (3) within one week, and (4) two weeks after TVUS. Clinical vaginal lubricants are similar to commercial lubricants, and often have a high osmolality or pH, and contain bactericides such as methylparaben and propylparaben. The number and maturity of epithelial cells in each CVF sample were measured by quantitative and differential fluorimetry (maturity index, MI). Comparisons of cell-counts and maturity were made by paired Wilcoxon signed-rank tests. Among women with a high pre-TVUS MI (> 3), there was a decrease in median cell-count and mean MI in the sample collected 6–12 hours after TVUS (pn = 26 and p < 0.001, n = 26, respectively). For these women, cell-count and MI remained lower in the sample collected within the subsequent week (pn = 29 and p<0.01, n = 29, respectively), and MI remained lower in the sample collected within two weeks of TVUS (pn = 25), compared to the pre-TVUS sample. Among participants with a low pre-TVUS MI (< 3), cell-count was higher in the sample collected within two weeks of TVUS compared to the pre-TVUS sample (p = 0.03, n = 15), but no significant changes in MI were observed. Results were similar when restricted to reproductive-age women. This preliminary data indicates hypertonic vaginal lubricants may increase vaginal epithelial cell shedding.

Background: Vulvovaginal candidiasis is commonly diagnosed and has been associated in prospective studies with the acquisition of HIV. Little data is available on how the composition of the vaginal microbiota, and other risk factors, are associated with the molecular detection of Candida albicans—a common cause of vulvovaginal candidiasis. Methods: In a cross-sectional study, self-collected vaginal swabs were obtained from 394 nonpregnant, reproductive-age women. C. albicans was detected using polymerase chain reaction targeting C. albicans ITS1/2 region. Vaginal microbiota was characterized by 16S rRNA gene amplicon sequencing of the V3 to V4 hypervariable regions and clustered into community state types (CSTs). Multiple logistic regression identified factors associated with C. albicans detection. Results: Twenty-one percent had C. albicans detected and 46% reported vaginal symptoms in the prior 60 days. There was a 2-fold increase in the odds of C. albicans if a woman was in a L. crispatus-dominated CST compared to CSTs with low-Lactobacillus levels (adjusted odds ratio, 2.05; 95% confidence interval, 0.97–4.37). History of self-treatment with antifungals, L. crispatus relative abundance, and receptive oral sex were also significantly associated with C. albicans detection. Conclusions: A L. crispatus-dominated vaginal microbiota is thought to protect women from both development of bacterial vaginosis and incidence of sexually transmitted infections; however, our data suggest that L. crispatus is associated with increased C. albicans detection. Receptive oral sex may also be a risk factor for vaginal C. albicans colonization.

We evaluated compliance with submitting a short Web-based personal behavior survey daily during a 10-week study (n = 52 women/3419 diaries). Time-stamped forms revealed that 50% of diaries were submitted within 24 hours of the email prompt, and 19% were missing or submitted more than 3 days late. Late submissions may affect data quality.