Bacterial vaginosis is associated with variation in dietary indices

The association between dietary phytochemical index and bacterial vaginosis risk: secondary analysis of case-control study

INTRODUCTION

By studying the dietary habits of patients with bacterial vaginosis (BV) and the controls, we aim to find out whether the dietary intakes of phytochemicals could reduce the odds of BV. To the best of our knowledge, no study has ever examined the matter before. Therefore, we decided to conduct this secondary analysis of case-control study to examine the association between dietary phytochemicals and BV.

METHOD

This case-control study was conducted at the gynecological clinic of Imam Hossein Hospital using a convenience sampling method from November 2020 to June 2021. To diagnose BV, all participants underwent examination by a gynecologist, assessing the presence of 3 or 4 criteria from the Amsel criteria. A validated semi-quantitative food frequency questionnaire was used. The phytochemical index was determined using McCarty's method. To assess the association between dietary phytochemical intake and the odds of BV, binary logistic regression was utilized.

RESULTS

After adjusting for potential confounders, the association between phytochemical index and BV remained significant (odds ratio (OR) = 0.349, 95% confidence interval (CI): 0.176-0.695, p-value = 0.003). Furthermore, each unit increase in fat intake was associated with higher odds of BV (OR = 1.008, 95% CI: 1.002-1.014, p-value = 0.006), and a positive family history of BV continued to show significantly increased odds of BV (OR = 3.442, 95% CI: 2.068-5.728, p-value < 0.001).

CONCLUSION

In summary, the findings of this study indicate that increased consumption of dietary phytochemicals is associated with a reduced risk of BV among Iranian women of reproductive age. Additional research, especially longitudinal dietary studies, is required to explore the potential impact of dietary modifications on BV.

Association between body mass index and prevalence of bacterial vaginosis: Results from the NHANES 2001-2004 study

BACKGROUND

The impact of bacterial vaginosis on women's health is an increasing concern; however, the effect of the obesity index on bacterial vaginosis is controversial. We investigated the association between body mass index and bacterial vaginosis in women in the United States.

METHODS

This was a cross-sectional study which obtained the data from the National Health and Nutrition Examination Survey from 2001 to 2004, in which weighted multivariate regression and logistic regression analyses were performed to explore the independent relationship between body mass index and bacterial vaginosis. Subgroup analyses and smoothed curve fitting were also performed.

RESULTS

A total of 5,428 participants were enrolled, and the findings show that the participants with higher body mass index tended to have a higher incidence of bacterial vaginosis. In the fully adjusted model, a positive association between bacterial vaginosis and body mass index was observed (Odd's ratio = 1.03, 95% Confidence interval, 1.01-1.04). The subgroup analysis showed that this positive association was significant in non-Hispanic White individuals (Odd's ratio = 1.0327, 95% Confidence interval, 1.0163, 1.0493).

CONCLUSION

Increased bacterial vaginosis positivity may be associated with an increased body mass index.

The effect of dietary habits on oocyte/sperm quality

The effects of diet and nutritional habits on reproductive cells can be categorized in a variety of ways. In this review, the literature is divided, based on the dietary consumption effects on oocytes and sperm. Topics on dietary patterns and the intrauterine effect of maternal nutrition are covered. In general fruits, vegetables, whole greens, fish, legumes, and also dietary sources containing unsaturated fats can improve reproductive germ cell quality. In epidemiological studies, the food intake frequency questionnaire is one of the most common methods to assess diet. Due to methodological heterogeneity in dietary assessment and inadequacy in the measurement of dietary intake in the questionnaires used, several unreliable results may be reported. Thus, the quality of evidence needs to be improved, since nutritional diets may not be so simply objective and they are inadequate to explain obvious underlining mechanisms. In addition, various compounds that may be ingested can affect molecular mechanisms, influenced by other external factors (drugs, pesticides, smoking, alcohol) and changes in human nutritional parameters. Artificial Intelligence has recently gained widespread interest and may have a role in accurate analysis of dietary patterns for optimal nutritional benefit. Therefore, future prospective randomized studies and objective measurements, consisting of molecular level analysis of the impact on cells and clear-cut methods are needed for accurate assessment of the effect of dietary habits on reproductive treatment.

Bacterial vaginosis: a review of approaches to treatment and prevention

Bacterial vaginosis (BV) is a common cause of vaginitis worldwide and is associated with serious reproductive health outcomes, including increased risk of preterm birth, sexually transmitted infections, and pelvic inflammatory disease. The current and only FDA-approved treatment regimens for BV are antibiotics, such as metronidazole and clindamycin. Antibiotics provide a short-term cure for bacterial vaginosis; however, fail to provide a consistent long-term cure for many women. Fifty to eighty percent of women experience a BV recurrence within a year of completing antibiotic treatment. This may be because after antibiotic treatment, beneficial strains of Lactobacillus, such as L. crispatus, do not recolonize the vagina. In the absence of an effective long-term cure, patients, providers, and researchers are exploring different approaches to treatment and prevention, resulting in a rapid evolution of perspectives on BV pathogenesis and approaches to management. Current areas of investigation for BV management include probiotics, vaginal microbiome transplantation, pH modulation, and biofilm disruption. Behavioral modifications that may help include smoking cessation, condom use and hormonal contraception. Additional strategies considered by many people include dietary modification, non-medical vaginally applied products, choice of lubricant, and treatments from medical practices outside of allopathic medicine. This review aims to provide a comprehensive and up to date outline of the landscape of ongoing and potential treatment and prevention strategies for BV.

Female reproductive tract-organ axes

The female reproductive tract (FRT) and remote/versatile organs in the body share bidirectional communication. In this review, we discuss the framework of the "FRT-organ axes." Each axis, namely, the vagina-gut axis, uterus-gut axis, ovary-gut axis, vagina-bladder axis, vagina-oral axis, uterus-oral axis, vagina-brain axis, uterus-brain axis, and vagina-joint axis, is comprehensively discussed separately. Each axis could be involved in the pathogenesis of not only gynecological diseases but also diseases occurring apart from the FRT. Although the microbiota is clearly a key player in the FRT-organ axes, more quantitative insight into the homeostasis of the microbiota could be provided by host function measurements rather than current microbe-centric approaches. Therefore, investigation of the FRT-organ axes would provide us with a multicentric approach, including immune, neural, endocrine, and metabolic aspects, for understanding the homeostatic mechanism of women's bodies. The framework of the FRT-organ axes could also provide insights into finding new therapeutic approaches to maintain women's health.

The Vaginal Microbiome in Health and Disease-What Role Do Common Intimate Hygiene Practices Play?

The vaginal microbiome is a dynamic, sensitive microenvironment. The hallmark of a 'healthy' vaginal microbiome is currently believed to be one dominated by Lactobacillus spp., which acidifies the vaginal environment and help to protect against invading pathogens. However, a 'normal' microbiome is often difficult, if not impossible, to characterise given that it varies in response to numerous variables, including pregnancy, the menstrual cycle, contraceptive use, diet, ethnicity, and stress. A Lactobacillus-depleted microbiome has been linked to a variety of adverse vaginal health outcomes, including preterm birth (PTB), bacterial vaginosis (BV), and increased risk of sexually transmitted infections. The latter two of these have also been associated with feminine intimate hygiene practices, many of which are practised without any evidence of health benefits. The most extensively studied practice is vaginal douching, which is known to cause vaginal dysbiosis, predisposing women to BV, pelvic inflammatory disease, and PTB. However, little is known of the impact that intimate hygiene practices and associated products have on the vaginal microbiome. This review aims to outline the major factors influencing the vaginal microbiome and common vaginal infections, as well as to summarise current research surrounding the impact of hygiene products and practices on the vaginal microbiome.

Dietary acid load, alternative healthy eating index score, and bacterial vaginosis: is there any association? A case-control study

Background:

Changing the dietary pattern may be an alternative treatment for bacterial vaginosis, the prevalent vaginal infection in women.

Methods:

One hundred and forty-three bacterial vaginosis-affected women diagnosed by Amsel criteria and 151 healthy controls aged 18 to 45 entered the current case-control research. To calculate the alternative healthy eating index and dietary acid load score, food consumption was recorded with an accurate and precise food frequency questionnaire. The dietary acid load was measured by potential renal acid load (PRAL) and net endogenous acid production (NEAP) indices. Using logistic regression models, the association between the alternative healthy eating index and dietary acid load score with bacterial vaginosis was investigated.

Results:

The last tertile of the alternative healthy eating index had a 75% decreased odds of experiencing bacterial vaginosis in the adjusted model (adjusted odds ratio (aOR) = 0.25, 95% confidence interval (CI) = 0.12–0.53, P for trend = 0.001). Besides, vegetables (aOR = 0.34, 95% CI = 0.17–0.69, P for trend = 0.003), nuts and legumes (aOR = 0.44, 95% CI = 0.23–0.87, P for trend = 0.028), and meats (aOR = 0.31, 95% CI = 0.16–0.60, P for trend = 0.001) intake was linked to a decreased bacterial vaginosis odds. However, sugar-sweetened beverages and fruit juice (aOR = 3.47, 95% CI = 1.68–7.17, P for trend < 0.001), trans fatty acids (aOR = 2.29, 95% CI = 1.18–4.43, P for trend = 0.005), and sodium (aOR = 3.44, 95% CI = 1.67–7.06, P for trend = 0.002) intake were directly associated with bacterial vaginosis odds. There was no evidence of a link between dietary acid load and bacterial vaginosis.

Conclusion:

According to the present study’s findings, there is no correlation between dietary acid load and the likelihood of developing bacterial vaginosis. However, following a plant-based dietary pattern based on the healthy eating index may lead to a lower odds of bacterial vaginosis.

Rapid Point-of-Care Test Kit for Bacterial Vaginosis: Detection of Vaginolysin and Clue Cells Using Paper Strips and a Smartphone

There is an unmet need for a point-of-care test that is accurate, affordable, and simple to diagnose bacterial vaginosis, the most common cause of vaginal symptoms among women. Bacterial vaginosis leaves patients with undesirable vaginal discharge, malodor, and discomfort. Currently, the diagnosis of bacterial vaginosis is inaccurate and complex, leading to high rates of misdiagnosis. Inaccurate diagnoses are unsafe as bacterial vaginosis increases the risks of acquiring sexually transmitted infections as well as the likelihood of miscarriages. To date, the most commonly identified bacteria associated with bacterial vaginosis is Gardnerella vaginalis. We developed a method for the expression, purification, and detection of vaginolysin, the most well-characterized virulence factor of G. vaginalis. Elevated levels of G. vaginalis have been shown to lead to a toxic vaginal environment, facilitating bacterial vaginosis. We have developed an enzyme-linked immunosorbent assay for the detection of vaginolysin, which was translated to a lateral flow assay for use in a rapid, straightforward, cost-effective paper-based diagnostic test for vaginolysin that does not require the use of instrumentation. In conjunction, we have employed a commercially available smartphone microscopy kit to visualize clue cells without the need for equipment or electricity. The combination of these methodologies allows for an accurate and easy approach to diagnose bacterial vaginosis with minimal resources for use in any setting.

Patterns of Pediatric and Adolescent Gynecologic Problems in China: A Hospital-Based Retrospective Study of 97,252 Patients

STUDY OBJECTIVE

To describe the pattern and population characteristics of pediatric and adolescent gynecologic (PAG) problems in China DESIGN: A clinic-based retrospective study of gynecologic patients (aged 0-18 years) over a period of 13 years SETTING: Department of PAG in the Children's Hospital, Zhejiang University School of Medicine PARTICIPANT: The final analyses included 97,252 patients with gynecologic problems.

INTERVENTIONS/METHODS

Descriptive analysis was conducted to evaluate the pattern of PAG problems.

MAIN OUTCOME MEASURES

Spectrum of PAG problems RESULTS AND CONCLUSIONS: The number of first-visit PAG patients increased from 4,582 to 11,876 from 2006 to 2018. Overall, genital inflammation was the most common presentation (57.0%), followed by precocious puberty (18.2%). The disease pattern varied across age groups; the most common problems were genital inflammation for age 0-6 years, genital inflammation and precocious puberty for age 7-9 years, and consultation, genital inflammation, and menstrual disorders for age 10-18 years. Overall, genital inflammation, precocious puberty, consultation, and menstrual disorders were common issues for pediatric and adolescent patients with gynecologic problems in China.

Association between dietary patterns and bacterial vaginosis: a case-control study

Bacterial vaginosis (BV) is a predominant vaginal disturbance that affects about 25% of childbearing-aged women. Dietary consumption may have a crucial role in vaginal flora imbalances. This study was a hospital-based case–control study. In total, 144 incident BV cases and 151 healthy participants were recruited from the gynecology clinic in Tehran, Iran, between November 2020 and June 2021. Participants' typical diets were collected by a food frequency questionnaire. Vaginal flora was characterized based on the Amsel criteria. Factor analysis was used to pinpoint the principal dietary patterns. For logistic regression, the first tertile was assumed as a reference. Five principal dietary patterns emerged and were nominated as "Healthy diet," "Unhealthy diet," "Ovo-vegetarian diet," "Pseudo-Mediterranean diet," and "Western diet." The "Unhealthy diet" pattern were positively associated with BV (adjusted odds ratio (aOR) = 3.35; 95% confidence interval (CI) 1.41, 7.94; p_trend: 0.006), while adherence to the "Ovo-vegetarian diet" pattern was associated with a reduced odds of BV (aOR = 0.16; 95% CI 0.07, 0.34; p_trend < 0.001). These results provide evidence that following the "unhealthy diet" pattern may lead to developing BV, and plant-based eating patterns may be associated with reduced BV odds.

Host and Microbiome Interplay Shapes the Vaginal Microenvironment

The female reproductive tract harbors a unique microbiome, especially the vagina. The human vaginal microbiome exhibits a low diversity and is dominated by Lactobacillus species, compared to the microbiome of other organs. The host and vaginal microbiome mutually coexist in the vaginal microenvironment. Host cells provide Lactobacillus glycogen as an energy source, and Lactobacillus produce lactic acid, which lowers vaginal pH thereby preventing growth of other bacteria. Bacterial vaginosis can modulate host immune systems, and is frequently associated with various aspects of disease, including sexually transmitted infection, gynecologic cancer, and poor pregnancy outcomes. Because of this, numerous studies focused on the impact of the vaginal microbiome on women`s health and disease. Furthermore, numerous epidemiologic studies also have demonstrated various host factors regulate the vaginal microbiome. The female reproductive tract undergoes constant fluctuations due to hormonal cycle, pregnancy, and other extrinsic factors. Depending on these fluctuations, the vaginal microbiome composition can shift temporally and dynamically. In this review, we highlight the current knowledge of how host factors modulate vaginal microbiome composition and how the vaginal microbiome contributes to maintaining homeostasis or inducing pathogenesis. A better understanding of relationship between host and vaginal microbiome could identify novel targets for diagnosis, prognosis, or treatment of microbiome-related diseases.

Is there any association between adherence to the Mediterranean Diet and Dietary Total Antioxidant Capacity with Bacterial Vaginosis? Results from a Case-Control study

Background

Bacterial vaginosis, BV, is a common inflammatory vaginal dysbiosis. The Mediterranean diet, MD, containing foods rich in antioxidant compounds, is shown to be beneficial for inflammatory conditions. This study aimed to investigate the association between MD adherence and dietary total antioxidant capacity (DTAC) with BV.

Methods

This case–control study was conducted on 143 BV-affected and 151 healthy individuals aged between 15 and 45 years. The Amsel criteria were used to detect newly diagnosed patients with BV by a gynecologist. The 168-item food frequency questionnaire (FFQ) was used to record participants' dietary intakes in the last year. The reported data in the FFQ was used to measure adherence to the MD by calculating the Medi-Lite score and to measure the DTAC by calculating ferric-reducing antioxidant power, FRAP, based on the related databases. Logistic regression models were used to determine the association between Medi-Lite and DTAC and BV odds.

Results

The highest tertile of Medi-Lite score was associated with a reduced odds of BV in the crude model (Odds Ratio, OR: 0.49, 95% Confidence Interval, 95% CI 0.25, 0.96, P for trend: 0.023). This significant inverse association was not observed in the last model adjusted for age, body mass index (kg/m²), waist circumferences (cm), cigarette smoking, frequency of pregnancy, and physical activity (MET/h/d). In crude and adjusted odels, BV odds decreased in the highest tertile of vegetable (adjusted OR, aOR: 0.32, 95% CI 0.16, 0.63, P for trend: 0.001), fish (aOR: 0.46, 95% CI 0.25, 0.84, P for trend: 0.009), legumes (aOR: 0.26, 95% CI 0.14, 0.50, P for trend < 0.001), and meat (aOR: 0.29, 95% CI 0.15, 0.56, P for trend < 0.001) groups. There was no significant association between DTAC and BV odds.

Conclusions

The significant inverse association between the MD adherence and BV odds did not remain after modifying for confounders; besides, DTAC was not associated with BV odds. However, some of the MD components might be associated with a reduced odds of BV.

The vaginal microbiome: A complex milieu affecting risk of human papillomavirus persistence and cervical cancer

The purpose of this review is to describe the existing literature regarding the relationship between the vaginal microbiome, human papillomavirus persistence, and cervical cancer risk, as well as to discuss factors that mediate these relationships. Data suggest that alterations in the vaginal microbiome affect the risk of human papillomavirus infection and persistence, which has downstream effects on cervical dysplasia and cancer risk. The homeostatic Lactobillus species L. crispatus, L. gasseri, L. jensenii act to promote a healthy vaginal environment, while L. iners and pathogens causing bacterial vaginosis are associated with increased inflammation, human papillomavirus infection, cervical dysplasia, and potentially cancer. There are, however, still several large gaps in the literature, particularly related to the modifiable and non-modifiable factors that affect the vaginal microbiome and ensuing risk of pre-cancerous and cancerous lesions. Evidence currently suggests that endogenous and exogenous hormones, tobacco products, and sexual practices influence vaginal microbiome composition, but the nuances of these relationships and how changes in these factors affect dysplasia risk are yet to be delineated. Other studies examining how diet, exercise, race, socioeconomic status, and genetic factors influence the vaginal microbiome are difficult to interpret in the setting of multiple confounders. Future studies should focus on how changes in these modulatory factors might promote a healthy vaginal microbiome to prevent or treat dysplasia in the lower female genital tract.

Healthy Vaginal Microbiota and Influence of Probiotics Across the Female Life Span

Vaginal microbiota plays a central role in women's health and reproduction. Vaginal microbiota is dynamic and shaped by hormonal shifts in each stage of a woman's life from pre-puberty to postmenopause. Current research has mainly focused on vaginal bacterial and fungal members of the community and emphasized their role in disease. However, the impact of balanced vaginal microbiota on health and its interaction with the host is yet poorly understood. High abundance of vaginal lactobacilli is most strongly associated with health, but the concept of health may vary as vaginal dysbiosis may be asymptomatic. Furthermore, there is a lot of variation between ethnic groups in terms of dominating vaginal bacteria. Probiotic lactobacilli could be a safe and natural means to balance and maintain healthy vaginal microbiota. Research evidence is accumulating on their role in supporting women's health throughout life. This review describes the current literature on vaginal microbiota, the major factors affecting its composition, and how the communities change in different life stages. Furthermore, we focused on reviewing available literature on probiotics and their impact on vaginal microbiota and health.

Association of Dietary Glycemic Index, Glycemic Load, Insulin Index, and Insulin Load with Bacterial Vaginosis in Iranian Women: A Case-Control Study

Background

Inconsistent findings have been reported for associations between dietary indices and bacterial vaginosis (BV). The aim of this study was to examine the association of dietary glycemic index (DGI), glycemic load (DGL), insulin index (DII), and insulin load (DIL) with BV among Iranian women.

Methods

The current case-control study consisted of 144 new cases of BV and 151 controls. The diagnosis of BV was made based on the Amsel criterion in hospital clinics in Tehran, Iran, from November 2020 until June 2021. DGI, DGL, DII, and DIL were calculated from a validated semiquantitative food frequency questionnaire. The association between dietary carbohydrate indices and odds of BV were assessed adjusting for potential confounders through an estimation of two multivariate regression models.

Results

The multivariate adjusted odds ratio (OR) comparing the highest tertile of dietary DGI and DGL with the lower tertile was 2.99 (95% confidence interval (CI): 1.47–6.81; P_trend = 0.003) and 4.01 (95% CI: 1.22–5.91; P_trend = 0.029), respectively. In a fully adjusted model, the top tertile of dietary fiber compared to the bottom was associated with 88% (95% CI: 0.14-0.33) lower odds of BV (P_trend < 0.001). DII and DIL were not significantly associated with odds of BV in both crude and adjusted regression models.

Conclusion

The findings support the hypothesis of moderate, direct associations between DGI or DGL and BV. Also, a diet high in fiber decreases odds of BV.

Is prenatal diet associated with the composition of the vaginal microbiome?

BACKGROUND

The vaginal microbiome has been associated with adverse pregnancy outcomes, but information on the impact of diet on microbiome composition is largely unexamined.

OBJECTIVE

To estimate the association between prenatal diet and vaginal microbiota composition overall and by race.

METHODS

We leveraged a racially diverse prenatal cohort of North Carolina women enrolled between 1995 and 2001 to conduct this analysis using cross-sectional data. Women completed food frequency questionnaires about diet in the previous 3 months and foods were categorised into subgroups: fruits, vegetables, nuts/seeds, whole grains, low-fat dairy, sweetened beverages and red meat. We additionally assessed dietary vitamin D, fibre and yogurt consumption. Stored vaginal swabs collected in mid-pregnancy were sequenced using 16S taxonomic profiling. Women were categorised into three groups based on predominance of species: Lactobacillus iners, Lactobacillus miscellaneous and Bacterial Vaginosis (BV)-associated bacteria. Adjusted Poisson models with robust variance estimators were run to assess the risk of being in a specific vagitype compared to the referent. Race-stratified models (Black/White) were also run.

RESULTS

In this study of 634 women, higher consumption of dairy was associated with increased likelihood of membership in the L. crispatus group compared to the L. iners group in a dose-dependent manner (risk ratio quartile 4 vs. 1: 2.01, 95% confidence interval 1.36, 2.95). Increased intake of fruit, vitamin D, fibre and yogurt was also associated with increased likelihood of membership in L. crispatus compared to L. iners, but only among black women. Statistical heterogeneity was only detected for fibre intake. There were no detected associations between any other food groups or risk of membership in the BV group.

CONCLUSIONS

Higher consumption of low-fat dairy was associated with increased likelihood of membership in a beneficial vagitype, potentially driven by probiotics.

Novel risk factors associated with common vaginal infections: a nationwide primary healthcare cohort study

OBJECTIVE

To estimate the association between potential risk factors and common vaginal infections, using nationwide primary healthcare and other national register.

METHODS

An open cohort study consisting of 2 357 711 women aged 15-50 years (2001-2018) was conducted in Sweden. The outcomes were first event of vulvovaginal candidiasis (VVC) and bacterial vaginosis (BV) in relation to sociodemographic factors. Cox regression models were used. Sensitivity analyses including diabetes mellitus, contraceptive use, and cervical cancer were conducted.

RESULTS

The incidence rates per 1000 person-years for VVC and BV were 3.3 (95% CI 3.2-3.3) and 3.4 (95% CI 3.4-3.4), respectively. In the fully adjusted model, sociodemographic factors were significantly associated with both outcomes. Compared to Swedish-born women, women from Middle East/North Africa had the highest risk of VVC (HR 2.77, 95% CI, 2.72-2.83), followed by Africa (excluding North Africa) (HR 2.53, 95% CI, 2.45-2.61), and Latin America and the Caribbean (HR 2.18, 95% CI, 2.09-2.27). For BV, women from Latin America and the Caribbean had the highest risk (HR 1.83, 95% CI, 1.75-1.92).

CONCLUSION

This study presents novel risk factors associated with medically attended vaginal infections. Women from non-western countries seem to suffer disproportionately from these conditions.

Pre-Pregnancy Diet and Vaginal Environment in Caucasian Pregnant Women: An Exploratory Study

Vaginal microbes and their metabolic products have crucial functions, affecting local immunity development and maternal-fetal health. The composition of the vaginal microbiome can vary in response to various factors, including body mass index (BMI), and diet. In this study we get new insights into the vaginal ecosystem of Caucasian women (n = 24) at the first trimester of pregnancy, assessing whether pre-pregnancy diet can affect the structure of the vaginal environment in terms of bacterial composition and vaginal metabolite concentration. We characterized 1) the vaginal bacterial composition (Nugent score), 2) the vaginal metabolic profiles (¹H-NMR spectroscopy), and 3) the dietary nutrient intake by means of a validated food frequency questionnaire. Pre-pregnancy BMI was negatively related to vaginal health status, indicating that women who begin pregnancy overweight/obese have a greater occurrence of vaginal dysbiosis during pregnancy. A lactobacilli-dominated vaginal microbiota was negatively associated with higher pre-pregnancy intake of animal-sourced protein. Conversely, a higher pre-pregnancy consumption of total carbohydrates and sugars seemed to be a protective factor for vaginal health. The vaginal environment of BV-women was characterized by higher levels of biogenic amines and organic acids, whereas higher levels of phenylpropionate and diverse amino acids were fingerprints of a healthy vaginal status. A significant association between a higher pre-pregnancy BMI and several dysbiosis-related vaginal metabolites was also found. Our study shed light on the role of pre-pregnancy BMI and diet on the vaginal environment during pregnancy, underlining the importance of limiting protein intake from animal foods to maintain a healthy lactobacilli-dominated microbiota.

Vaginal microbiome: normalcy vs dysbiosis

It has been long understood that the vaginal microflora is crucial in maintaining a normal physiological environment for the host and its involvement is deemed indispensable for reproductive success. A global concept of normalcy vs. dysbiosis of vaginal microbiome is debatable as women of different races have a unique vaginal microflora with regional variations. Vaginal microflora is a dynamic microenvironment affected by gestational status, menstrual cycle, sexual activity, age, and contraceptive use. Normal vaginal flora is dominated by lactobacilli especially in women of European descent vs. African American women. These microbes confer the host vagina protection from potentially pathogenic microbes that may lead to urinary tract infections and sexually transmitted diseases. Changes in the vaginal microbiota including reduced lactobacilli abundance and increased facultative and anaerobic organism populations result in bacterial vaginosis, that predisposes the host to several conditions like low birth weight and increased risk of contracting bacterial infections. On the other hand, the vaginal microbiome is also reshaped during pregnancy, with less microbial diversity with a dominance of Lactobacillus species. However, an altered vaginal microbiota with low lactobacilli abundance especially during pregnancy may result in induction of excessive inflammation and pre-term labor. Since the vaginal microbiome plays an important role during embryo implantation, it is not surprising that bacterial vaginosis is more common in infertile women and associated with reduced rates of conception. Probiotic has great success in treating bacterial vaginosis and restoring the normal microbiome in recent. This report, reviewed the relationships between the vaginal microbiome and women's reproductive health.

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.

Nutrition in Gynecological Diseases: Current Perspectives

Diet and nutrition are fundamental in maintaining the general health of populations, including women's health. Health status can be affected by nutrient deficiency and vice versa. Gene-nutrient interactions are important contributors to health management and disease prevention. Nutrition can alter gene expression, as well as the susceptibility to diseases, including cancer, through several mechanisms. Gynecological diseases in general are diseases involving the female reproductive system and include benign and malignant tumors, infections, and endocrine diseases. Benign diseases such as uterine fibroids and endometriosis are common, with a negative impact on women's quality of life, while malignant tumors are among the most common cause of death in the recent years. In this comprehensive review article, a bibliographic search was performed for retrieving information about nutrients and how their deficiencies can be associated with gynecological diseases, namely polycystic ovary syndrome, infertility, uterine fibroids, endometriosis, dysmenorrhea, and infections, as well as cervical, endometrial, and ovarian cancers. Moreover, we discussed the potential beneficial impact of promising natural compounds and dietary supplements on alleviating these significant diseases.

Interaction between dietary branched-chain amino acids and genetic risk score on the risk of type 2 diabetes in Chinese

BACKGROUND AND OBJECTIVES

Previous studies have found the important gene-diet interactions on type 2 diabetes (T2D) incident but have not followed branched-chain amino acids (BCAAs), even though they have shown heterogeneous effectiveness in diabetes-related factors. So in this study, we aim to investigate whether dietary BCAAs interact with the genetic predisposition in relation to T2D risk and fasting glucose in Chinese adults.

METHODS

In a case-control study nested in the Harbin Cohort Study on Diet, Nutrition and Chronic Non-Communicable Diseases, we obtained data for 434 incident T2D cases and 434 controls matched by age and sex. An unweighted genetic risk score (GRS) was calculated for 25 T2D-related single nucleotide polymorphisms by summation of the number of risk alleles for T2D. Multivariate logistic regression models and general linear regression models were used to assess the interaction between dietary BCAAs and GRS on T2D risk and fasting glucose.

RESULTS

Significant interactions were found between GRS and dietary BCAAs on T2D risk and fasting glucose (p for interaction = 0.001 and 0.004, respectively). Comparing with low GRS, the odds ratio of T2D in high GRS were 2.98 (95% CI 1.54-5.76) among those with the highest tertile of total BCAA intake but were non-significant among those with the lowest intake, corresponding to 0.39 (0.12) mmol/L versus - 0.07 (0.10) mmol/L fasting glucose elevation per tertile. Viewed differently, comparing extreme tertiles of dietary BCAAs, the odds ratio (95% CIs) of T2D risk were 0.46 (0.22-0.95), 2.22 (1.15-4.31), and 2.90 (1.54-5.47) (fasting glucose elevation per tertile: - 0.23 (0.10), 0.18 (0.10), and 0.26 (0.13) mmol/L) among participants with low, intermediate, and high genetic risk, respectively.

CONCLUSIONS

This study indicated that dietary BCAAs could amplify the genetic association with T2D risk and fasting glucose. Moreover, higher BCAA intake showed positive association with T2D when genetic predisposition was also high but changed to negative when genetic predisposition was low.

Determinants of Vaginal Microbiota Composition

There is increasing evidence that the composition of a woman's vaginal microbiota significantly influences her sexual and reproductive health, including her risk of miscarriage, preterm birth, HIV and other sexually transmitted infections. Efforts to modulate the vaginal microbiota using antibiotic or probiotic therapy have shown limited lasting or reliable success. To explore the natural dynamics and causal pathways responsible for heterogeneity of vaginal microbiota composition we review the existing literature on its determinants, from the perspective of microorganism- and host-related factors. We then discuss how molecular approaches can be harnessed to advance our understanding of individual and population-level vaginal microbiota composition patterns. Work has been done to investigate determinants of microbial composition patterns in other body niches, but very little in the female genital tract so far. There is an urgent need to better understand vaginal microbiota composition patterns, across the lifespan, outside of the context of sexual health clinics, and in Sub-Saharan African women in whom vaginal microbiota composition may be a risk factor for HIV acquisition. More work is needed to clarify causal relationships between clinical symptoms, host genetic, host behavior, and molecular vaginal microbiota profiles. These insights will lay the groundwork for novel and targeted interventional approaches to improve women's sexual and reproductive health.

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.

Temporal Dynamics of the Adult Female Lower Urinary Tract Microbiota

Temporal dynamics of certain human microbiotas have been described in longitudinal studies; variability often relates to modifiable factors or behaviors. Early studies of the urinary microbiota preferentially used samples obtained by transurethral catheterization to minimize vulvovaginal microbial contributions. Whereas voided specimens are preferred for longitudinal studies, the few studies that reported longitudinal data were limited to women with lower urinary tract (LUT) symptoms, due to ease of accessing a clinical population for sampling and the impracticality and risk of collecting repeated catheterized urine specimens in a nonclinical population. Here, we studied the microbiota of the LUT of nonsymptomatic, premenopausal women using midstream voided urine (MSU) specimens to investigate relationships between microbial dynamics and personal factors. Using 16S rRNA gene sequencing and a metaculturomics method called expanded quantitative urine culture (EQUC), we characterized the microbiotas of MSU and periurethral swab specimens collected daily for approximately 3 months from a small cohort of adult women. Participants were screened for eligibility, including the ability to self-collect paired urogenital specimens prior to enrollment. In this population, we found that measures of microbial dynamics related to specific participant-reported factors, particularly menstruation and vaginal intercourse. Further investigation of the trends revealed differences in the composition and diversity of LUT microbiotas within and across participants. These data, in combination with previous studies showing relationships between the LUT microbiota and LUT symptoms, suggest that personal factors relating to the genitourinary system may be an important consideration in the etiology, prevention, and/or treatment of LUT disorders.IMPORTANCE Following the discovery of the collective human urinary microbiota, important knowledge gaps remain, including the stability and variability of this microbial niche over time. Initial urinary studies preferentially utilized samples obtained by transurethral catheterization to minimize contributions from vulvovaginal microbes. However, catheterization has the potential to alter the urinary microbiota; therefore, voided specimens are preferred for longitudinal studies. In this report, we describe microbial findings obtained by daily assessment over 3 months in a small cohort of adult women. We found that, similarly to vaginal microbiotas, lower urinary tract (LUT) microbiotas are dynamic, with changes relating to several factors, particularly menstruation and vaginal intercourse. Our study results show that LUT microbiotas are both dynamic and resilient. They also offer novel opportunities to target LUT microbiotas by preventative or therapeutic means, through risk and/or protective factor modification.

The microbiome and gynaecological cancer development, prevention and therapy

The female reproductive tract (FRT), similar to other mucosal sites, harbours a site-specific microbiome, which has an essential role in maintaining health and homeostasis. In the majority of women of reproductive age, the microbiota of the lower FRT (vagina and cervix) microenvironment is dominated by Lactobacillus species, which benefit the host through symbiotic relationships. By contrast, the upper FRT (uterus, Fallopian tubes and ovaries) might be sterile in healthy individuals or contain a low-biomass microbiome with a diverse mixture of microorganisms. When dysbiosis occurs, altered immune and metabolic signalling can affect hallmarks of cancer, including chronic inflammation, epithelial barrier breach, changes in cellular proliferation and apoptosis, genome instability, angiogenesis and metabolic dysregulation. These pathophysiological changes might lead to gynaecological cancer. Emerging evidence shows that genital dysbiosis and/or specific bacteria might have an active role in the development and/or progression and metastasis of gynaecological malignancies, such as cervical, endometrial and ovarian cancers, through direct and indirect mechanisms, including modulation of oestrogen metabolism. Cancer therapies might also alter microbiota at sites throughout the body. Reciprocally, microbiota composition can influence the efficacy and toxic effects of cancer therapies, as well as quality of life following cancer treatment. Modulation of the microbiome via probiotics or microbiota transplant might prove useful in improving responsiveness to cancer treatment and quality of life. Elucidating these complex host-microbiome interactions, including the crosstalk between distal and local sites, will translate into interventions for prevention, therapeutic efficacy and toxic effects to enhance health outcomes for women with gynaecological cancers.

A Prospective Cohort Study of the Association Between Body Mass Index and Incident Bacterial Vaginosis

Some studies suggest that higher body mass index is associated with increased susceptibility to bacterial vaginosis (BV), but results are conflicting.

METHODS

Female sex workers aged 16 to 45 years and participating in an open, prospective cohort study in Mombasa, Kenya between 2000 and 2014 were included in this analysis. Up to 2 years of follow-up were included per woman. Body mass index (BMI) was categorized as underweight (≤18.5), normal (18.5-24.9), overweight (25-29.9), and obese (≥30). Bacterial vaginosis was assessed using Nugent scores. Generalized estimating equations were used to estimate relative risks of the association between BMI and BV.

RESULTS

At baseline, 32.1% (n = 625) of 1946 women had BV. Half of women were overweight (31.1%, n = 606) or obese (20.1%, n = 391). Participants contributed 14,319 follow-up visits. Adjusting for age, compared to women with normal BMI, overweight (adjusted relative risk, 0.91; 95% confidence interval, 0.81-1.02) and obese (adjusted relative risk, 0.82; 95% confidence interval, 0.71-0.94) women were at lower risk for BV (joint P = 0.03).

CONCLUSIONS

Obese women had a nearly 20% lower risk of BV compared with women with normal BMI. Potential mechanisms for this effect, including possible effects of diet, obesity-associated changes in the gut microbiome, and systemic estrogen levels, should be explored.

Reviewing the Composition of Vaginal Microbiota: Inclusion of Nutrition and Probiotic Factors in the Maintenance of Eubiosis

The vaginal microbiota has importance in preserving vaginal health and defending the host against disease. The advent of new molecular techniques and computer science has allowed researchers to discover microbial composition in depth and associate the structure of vaginal microbial communities. There is a consensus that vaginal flora is grouped into a restricted number of communities, although the structure of the community is constantly changing. Certain Community-State Types (CSTs) are more associated with poor reproductive outcomes and sexually transmitted diseases (STDs) meanwhile, CSTs dominated by Lactobacillus species—particularly Lactobacillus crispatus—are more related to vaginal health. In this work, we have reviewed how modifiable and non-modifiable factors may affect normal vaginal microbiota homeostasis—including sexual behavior, race or ethnicity, and hygiene. Special interest has been given to how the use of probiotics, diet intake, and use of hormone replacement therapies (HRTs) can potentially impact vaginal microbiota composition.

Associations between dietary micronutrient intake and molecular-Bacterial Vaginosis

OBJECTIVES

Bacterial vaginosis (BV), a clinical condition characterized by decreased vaginal Lactobacillus spp., is difficult to treat. We examined associations between micronutrient intake and a low-Lactobacillus vaginal microbiota as assessed by molecular methods (termed "molecular-BV").

METHODS

This cross-sectional analysis utilized data collected at the baseline visit of the Hormonal Contraception Longitudinal Study, a cohort of reproductive-aged women followed over 2 years while initiating or ceasing hormonal contraception (HC). The Block Brief 2000 Food Frequency Questionnaire was administered and micronutrient intakes were ranked. Vaginal microbiota composition was assessed using 16S rRNA gene amplicon sequencing and clustered into community state types (CSTs) based on the types and relative abundance of bacteria detected. Associations between the lowest estimated quartile intake of nutrients and having a low-Lactobacillus CST (molecular-BV) were evaluated by logistic regression. Separate models were built for each nutrient controlling for age, body mass index, behavioral factors, HC use and total energy intake. We also conducted a literature review of existing data on associations between micronutrient intakes and BV.

RESULTS

Samples from 104 women were included in this analysis. Their mean age was 25.8 years (SD 4.3), 29.8% were African American, 48.1% were using HC, and 25% had molecular-BV. In adjusted multivariable analyses, the lowest quartile of betaine intake was associated with an increased odds of molecular-BV (aOR 9.2, p value < 0.01, [CI 2.4-35.0]).

CONCLUSIONS

This is the first study to assess the association between estimated micronutrient intake and molecular-BV. Lower energy-adjusted intake of betaine was associated with an increased risk of molecular-BV. Betaine might have direct effects on the vaginal microenvironment or may be mediated through the gut microbiota. Additional research is needed to determine reproducibility of this finding and whether improved intake of select micronutrients such as betaine decreases the risk of BV and its sequelae.

Association between obesity and bacterial vaginosis as assessed by Nugent score

BACKGROUND

Bacterial vaginosis is 1 of the most common vaginal conditions in the United States. Recent studies have suggested that obese women have an abnormal microbiota reminiscent of bacterial vaginosis; however, few studies have investigated the prevalence of bacterial vaginosis in overweight and obese populations. Moreover, despite the increased prevalence of obesity and bacterial vaginosis in black women, it is not known whether racial disparities exist in the relationship between obesity and bacterial vaginosis.

OBJECTIVE

The objective of this study was to examine the relationship between body mass index and bacterial vaginosis as determined by Nugent score and to determine the influence of race in this context.

STUDY DESIGN

We performed a cross-sectional study using patient data and vaginal smears from 5918 participants of the Contraceptive CHOICE Project. Gram-stained vaginal smears were scored with the Nugent method and categorized as bacterial vaginosis-negative (Nugent score, 0-3), bacterial vaginosis-intermediate (Nugent score, 4-6), or bacterial vaginosis-positive (Nugent score, 7-10). Body mass index was determined with Centers for Disease Control and Prevention guidelines, and obese individuals were categorized as class I, II, or III obese based on National Institutes of Health and World Health Organization body mass index parameters. Linear regression was used to model mean differences in Nugent scores; Poisson regression with robust error variance was used to model prevalence of bacterial vaginosis.

RESULTS

In our cohort, 50.7% of participants were black; 41.5% were white, and 5.1% were of Hispanic ethnicity; the average age of 25.3 years old. Overall, 28.1% of participants were bacterial vaginosis-positive. Bacterial vaginosis was prevalent in 21.3% of lean, 30.4% of overweight, and 34.5% of obese women (P<.001). The distribution of bacterial vaginosis-intermediate individuals was similar across all body mass index categories. Compared with the scores of lean women, Nugent scores were highest among overweight and obese class I women (adjusted mean difference: overweight women, 0.33 [95% confidence interval, 0.14-0.51] and obese women, 0.51 [95% confidence interval, 0.29-0.72]). Consistent with this, overweight and obese women had a higher frequency of bacterial vaginosis compared with lean women, even after adjustment for variables that included race. Among white women, the prevalence of bacterial vaginosis was higher for overweight and class I and class II/III obese white women compared with lean white women, which is a phenomenon not observed among black women and suggests an effect modification.

CONCLUSION

Overweight and obese women have higher Nugent scores and a greater occurrence of bacterial vaginosis compared with lean women. Black women have a greater prevalence of bacterial vaginosis independent of their body mass index compared with white women.

Use of copper intrauterine device is not associated with higher bacterial vaginosis prevalence in Thai HIV-positive women

The study assessed and compared bacterial vaginosis (BV) prevalence in Thai women in reproductive age in four study groups - group 1, HIV-positive with copper intrauterine device (Cu-IUD); group 2, HIV-positive without Cu-IUD; group 3, HIV-negative with Cu-IUD; and group 4, HIV-negative without Cu-IUD. We conducted a cross-sectional study. BV prevalence was assessed by Nugent score and Amsel criteria. Descriptive statistics was used to present baseline characteristics; kwallis rank test - to compare variables between the four groups; logistic regression - to assess factors, related to BV prevalence. The analysis included 137 women in the four study groups with a median age of 39 years. Median BV prevalence by Nugent score was 45%, intermediate vaginal flora - 7% and normal vaginal flora - 48%. There was no statistically significant difference in the BV prevalence between the four study groups, p = 0.711. Threefold lower BV prevalence was found, assessed by Amsel criteria compared to Nugent score. Women with body mass index (BMI) < 20 had higher probability to have BV or intermediate vaginal flora, OR = 3.11, 95% CI (1.2-8.6), p = 0.025. The study found a high BV prevalence in the four study groups, related neither to HIV status, nor to Cu-IUD use. BV prevalence was associated only with low BMI. Thus, Cu-IUD could be a good contraceptive choice for HIV-positive women. Research in defining normal vaginal microbiota and improve diagnostic methods for BV should continue.

Effects of long-term weekly iron and folic acid supplementation on lower genital tract infection - a double blind, randomised controlled trial in Burkina Faso

BACKGROUND

Provision of routine iron supplements to prevent anaemia could increase the risk for lower genital tract infections as virulence of some pathogens depends on iron availability. This trial in Burkina Faso assessed whether weekly periconceptional iron supplementation increased the risk of lower genital tract infection in young non-pregnant and pregnant women.

METHODS

Genital tract infections were assessed within a double blind, controlled, non-inferiority trial of malaria risk among nulliparous women, randomised to receive either iron and folic acid or folic acid alone, weekly, under direct observation for 18 months. Women conceiving during this period entered the pregnancy cohort. End assessment (FIN) for women remaining non-pregnant was at 18 months. For the pregnancy cohort, end assessment was at the first scheduled antenatal visit (ANC1). Infection markers included Nugent scores for abnormal flora and bacterial vaginosis (BV), T. vaginalis PCR, vaginal microbiota, reported signs and symptoms, and antibiotic and anti-fungal prescriptions. Iron biomarkers were assessed at baseline, FIN and ANC1. Analysis compared outcomes by intention to treat and in iron replete/deficient categories.

RESULTS

A total of 1954 women (mean 16.8 years) were followed and 478 (24.5%) became pregnant. Median supplement adherence was 79% (IQR 59-90%). Baseline BV prevalence was 12.3%. At FIN and ANC1 prevalence was 12.8% and 7.0%, respectively (P < 0.011). T. vaginalis prevalence was 4.9% at FIN and 12.9% at ANC1 (P < 0.001). BV and T. vaginalis prevalence and microbiota profiles did not differ at trial end-points. Iron-supplemented non-pregnant women received more antibiotic treatments for non-genital infections (P = 0.014; mainly gastrointestinal infections (P = 0.005), anti-fungal treatments for genital infections (P = 0.014) and analgesics (P = 0.008). Weekly iron did not significantly reduce iron deficiency prevalence. At baseline, iron-deficient women were more likely to have normal vaginal flora (P = 0.016).

CONCLUSIONS

Periconceptional weekly iron supplementation of young women did not increase the risk of lower genital tract infections but did increase general morbidity in the non-pregnant cohort. Unabsorbed gut iron due to malaria could induce enteric infections, accounting for the increased administration of antibiotics and antifungals in the iron-supplemented arm. This finding reinforces concerns about routine iron supplementation in highly malarious areas.

TRIAL REGISTRATION

Trial registration number NCT01210040 . Registered with Clinicaltrials.gov on 27 September 2010.

Vaginal Microbiome and Its Relationship to Behavior, Sexual Health, and Sexually Transmitted Diseases

The vaginal microbiota has great significance in maintaining vaginal health and protecting the host from disease. Recent advances in molecular techniques and informatics allow researchers to explore microbial composition in detail and to compare the structure of vaginal microbial communities with behavior and health outcomes, particularly acquisition and transmission of sexually transmitted diseases (STDs) and poor birth outcomes. Vaginal flora have been found to cluster into a limited number of communities, although community structure is dynamic. Certain community types are more associated with poor reproductive outcomes and STDs; communities dominated by Lactobacillus species, particularly Lactobacillus crispatus, are most associated with vaginal health. Modifiable and nonmodifiable factors are strongly associated with community composition, including behavior, race or ethnicity, and hygiene. In this review, we describe the state of the science on the vaginal microbiome and its relationship to behavior, sexual health, and STDs, including determinants of the microbiome that go beyond an individual level.

Lactobacilli Dominance and Vaginal pH: Why Is the Human Vaginal Microbiome Unique?

The human vaginal microbiome is dominated by bacteria from the genus Lactobacillus, which create an acidic environment thought to protect women against sexually transmitted pathogens and opportunistic infections. Strikingly, lactobacilli dominance appears to be unique to humans; while the relative abundance of lactobacilli in the human vagina is typically >70%, in other mammals lactobacilli rarely comprise more than 1% of vaginal microbiota. Several hypotheses have been proposed to explain humans' unique vaginal microbiota, including humans' distinct reproductive physiology, high risk of STDs, and high risk of microbial complications linked to pregnancy and birth. Here, we test these hypotheses using comparative data on vaginal pH and the relative abundance of lactobacilli in 26 mammalian species and 50 studies (N = 21 mammals for pH and 14 mammals for lactobacilli relative abundance). We found that non-human mammals, like humans, exhibit the lowest vaginal pH during the period of highest estrogen. However, the vaginal pH of non-human mammals is never as low as is typical for humans (median vaginal pH in humans = 4.5; range of pH across all 21 non-human mammals = 5.4-7.8). Contrary to disease and obstetric risk hypotheses, we found no significant relationship between vaginal pH or lactobacilli relative abundance and multiple metrics of STD or birth injury risk (P-values ranged from 0.13 to 0.99). Given the lack of evidence for these hypotheses, we discuss two alternative explanations: the common function hypothesis and a novel hypothesis related to the diet of agricultural humans. Specifically, with regard to diet we propose that high levels of starch in human diets have led to increased levels of glycogen in the vaginal tract, which, in turn, promotes the proliferation of lactobacilli. If true, human diet may have paved the way for a novel, protective microbiome in human vaginal tracts. Overall, our results highlight the need for continuing research on non-human vaginal microbial communities and the importance of investigating both the physiological mechanisms and the broad evolutionary processes underlying human lactobacilli dominance.

"I just think that doctors need to ask more questions": Sexual minority and majority adolescents' experiences talking about sexuality with healthcare providers

OBJECTIVE

To examine adolescent and young adults' experiences of sexuality communication with physicians, and gain advice for improving interactions.

METHODS

Semi-structured interviews were conducted with questions focusing on: puberty, romantic attractions, sexual orientation, dating, sexual behavior, clinical environment, and role of parents. Interviews were transcribed and analyzed using thematic analysis with both open and axial coding.

RESULTS

Five themes emerged from interviews: 1) need for increased quantity of sexual communication, 2) issues of confidentiality/privacy, 3) comfort (physician discomfort, physical space), 4) inclusivity (language use, gender-fluid patients, office environment), 5) need for increased quality of sexual communication.

CONCLUSIONS

Sexual minority and majority adolescents and young adults indicate sexuality discussions with physicians are infrequent and need improvement. They indicate language use and clinical physical environment are important places where physicians can show inclusiveness and increase comfort.

PRACTICE IMPLICATIONS

Physicians should make an effort to include sexual communication at every visit. They should consider using indirect questions to assess sexual topics, provide other outlets for sexual health information, and ask parents to leave the exam room to improve confidentiality. Clinic staff should participate in Safe Zone trainings, and practices can promote inclusion with signs that indicate safe and accepting environments.

Vaginal microbiome and metabolome highlight specific signatures of bacterial vaginosis

In this study, we sought to find novel bacterial and metabolic hallmarks for bacterial vaginosis (BV). We studied the vaginal microbiome and metabolome of vaginal fluids from BV-affected patients (n = 43) and healthy controls (n = 37) by means of an integrated approach based on quantitative polymerase chain reaction (qPCR) and proton nuclear magnetic resonance ((1)H-NMR). The correlations between the clinical condition and vaginal bacterial communities were investigated by principal component analysis (PCA). To define the metabolomics signatures of BV, 100 discriminant analysis by projection on latent structure (PLS-DA) models were calculated. Bacterial signatures distinguishing the health condition and BV were identified by qPCR. Lactobacillus crispatus strongly featured the healthy vagina, while increased concentrations of Prevotella, Atopobium and Mycoplasma hominis specifically marked the infection. (1)H-NMR analysis has led to the identification and quantification of 17 previously unreported molecules. BV was associated with changes in the concentration of metabolites belonging to the families of amines, organic acids, short chain fatty acids, amino acids, nitrogenous bases and monosaccharides. In particular, maltose, kynurenine and NAD(+) primarily characterised the healthy status, while nicotinate, malonate and acetate were the best metabolic hallmarks of BV. This study helps to better understand the role of the vaginal microbiota and metabolome in the development of BV infection. We propose a molecular approach for the diagnosis of BV based on quantitative detection in the vaginal fluids of Atopobium, Prevotella and M. hominis, and nicotinate, malonate and acetate by combining qPCR and (1)H-NMR.

Bacterial vaginosis in the context of lichen sclerosus in a prepubertal girl

Group A beta-hemolytic streptococcus cause most vulvovaginal infections seen in prepubertal girls. Bacterial vaginosis is a common cause of abnormal vaginal discharge in women of childbearing age but is rare in children. Data are insufficient to suggest that bacterial vaginosis is an exclusively sexually transmitted disease. We report a 10-year-old girl with no history or suspicion of sexual abuse who developed bacterial vaginosis in the context of a lichen sclerosus being treated with tacrolimus ointment. Secondary bacterial infection in lichen sclerosus is uncommon. We speculate that the immunosuppressive effect of topical tacrolimus could have triggered the infection.