Effects of oral contraceptive pill use on vaginal flora and vaginal epithelium

Comparison of Combined Parenteral and Oral Hormonal Contraceptives: A Systematic Review and Meta-Analysis of Randomized Trials

BACKGROUND

Delivering contraceptive hormones through a transdermal patch or a vaginal ring might have advantages over the traditional oral route.

OBJECTIVES

To compare the effectiveness, compliance, and side effect profile of oral and parenteral drug administration methods.

METHODS

We performed a systematic literature search in four medical databases-MEDLINE (via PubMed), Cochrane Library (CENTRAL), Embase, and Scopus-from inception to 20 November 2022. Randomized controlled trials assessing the efficacy, compliance, and adverse event profile of combined parenteral and oral hormonal contraceptives were included.

RESULTS

Our systematic search provided 3952 records; after duplicate removal, we screened 2707 duplicate-free records. A total of 13 eligible studies were identified after title, abstract, and full-text selection. We observed no significant difference in contraceptive efficacy (Pearl Index) between oral and parenteral drug administration (MD = -0.06, CI: -0.66-0.53; I2 = 0%). We found significant subgroup differences between parenteral methods in terms of compliance (χ2 = 4.32, p =0.038, I2 = 80%) and certain adverse events: breast discomfort (χ2 = 19.04, p =0.001, I2 = 80%), nausea (χ2 = 8.04, p =0.005, I2 = 75%), and vomiting (χ2 = 9.30, p =0.002; I2 = 72%).

CONCLUSION

Both parenteral and oral contraceptives can be used as an effective contraceptive method, and the route of administration should be tailored to patient needs and adverse event occurrence.

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.

Vaginal microbiome in obesity and its impact on reproduction

A number of reproductive outcomes have been increasingly found to be affected by the vaginal microbiota. Obesity has become a global epidemic, affecting increasing numbers of reproductive-age women, and has been shown to be a risk factor for a number of adverse female health outcomes. A healthy vaginal microbiome is characterized by Lactobacillus-dominance, in particular Lactobacillus crispatus; obesity has been found to be associated with higher diversity and a lower likelihood of Lactobacillus-dominance. In this review, we summarize the evidence on the vaginal microbiome in obese women and the impact on reproductive outcomes such as conception rates, early pregnancy, and preterm birth. We further explore the mechanisms by which obesity may result in an altered microbial composition and highlight future avenues for therapeutic targeting of the vaginal microbiota.

Microbiota Ecosystem in Recurrent Cystitis and the Immunological Microenvironment of Urothelium

Urinary tract infections (UTIs) represent one of the most frequent low genital tract diseases in the female population. When UTIs occur with a frequency of at least three times per year or two times in the last six month, we speak of recurrent UTI (rUTI) and up to 70% of women will have rUTI within 1 year. It was previously thought that antibiotic resistance was principally responsible for the recurrence of UTIs, but nowadays new diagnostic technologies have shown the role of microbiota in the pathophysiology of these diseases. Much research has been conducted on the role of gut microbiome in the development of rUTI, while little is known yet about vaginal and urinary microbiome and the possible immunological and microscopical mechanisms through which they trigger symptoms. New discoveries and clinical perspectives are arising, and they all agree that a personalized, multi-modal approach, treating vaginal and urinary dysbiosis, may reduce rUTIs more successfully.

Contraceptive exposure associates with urinary tract infection risk in a cohort of reproductive-age women: a case control study

PURPOSE

Although non-barrier contraception is commonly prescribed, the risk of urinary tract infections (UTI) with contraceptive exposure is unclear.

MATERIALS AND METHODS

Using data from Vanderbilt University Medical Centre's deidentified electronic health record (EHR), women ages 18-52 were randomly sampled and matched based on age and length of EHR. This case-control analysis tested for association between contraception exposure and outcome using UTI-positive (UTI+) as cases and upper respiratory infection+ (URI+) as controls.

RESULTS

24,563 UTI + cases (mean EHR: 64.2 months; mean age: 31.2 years) and 48,649 UTI-/URI + controls (mean EHR: 63.2 months; mean age: 31.9 years) were analysed. In the primary analysis, UTI risk was statistically significantly increased for the oral contraceptive pill (OCP; OR = 1.10 [95%CI = 1.02-1.11], p ≤ 0.05), intrauterine device (IUD; OR = 1.13 [95%CI = 1.04-1.23], p ≤ 0.05), etonogestrel implant (Nexplanon^®; OR = 1.56 [95% CI = 1.24-1.96], p ≤ 0.05), and medroxyprogesterone acetate injectable (Depo-Provera^®; OR = 2.16 [95%CI = 1.99-2.33], p ≤ 0.05) use compared to women not prescribed contraception. A secondary analysis that included any non-IUD contraception, which could serve as a proxy for sexual activity, demonstrated a small attenuation for the association between UTI and IUD (OR = 1.09 [95%CI = 0.98-1.21], p = 0.13).

CONCLUSION

This study notes potential for a small increase in UTIs with contraceptive use. Prospective studies are required before this information is applied in clinical settings.

CONDENSATION

Although non-barrier contraception is commonly prescribed, the risk of urinary tract infections (UTI) with contraceptive exposure is poorly understood. This large-cohort, case-control study notes potential for a small increase in UTIs with contraceptive use.

Vaginal Microbiome in Reproductive Medicine

The human microbiome has been given increasing importance in recent years. The establishment of sequencing-based technology has made it possible to identify a large number of bacterial species that were previously beyond the scope of culture-based technologies. Just as microbiome diagnostics has emerged as a major point of focus in science, reproductive medicine has developed into a subject of avid interest, particularly with regard to causal research and treatment options for implantation failure. Thus, the vaginal microbiome is discussed as a factor influencing infertility and a promising target for treatment options. The present review provides an overview of current research concerning the impact of the vaginal microbiome on the outcome of reproductive measures. A non-Lactobacillus-dominated microbiome was shown to be associated with dysbiosis, possibly even bacterial vaginosis. This imbalance has a negative impact on implantation rates in assisted reproductive technologies and may also be responsible for habitual abortions. Screening of the microbiome in conjunction with antibiotic and/or probiotic treatment appears to be one way of improving pregnancy outcomes.

The Vaginal Microbiome: III. The Vaginal Microbiome in Various Urogenital Disorders

OBJECTIVE

This series of articles, titled The Vaginal Microbiome (VMB), written on behalf of the International Society for the Study of Vulvovaginal Disease, aims to summarize the recent findings and understanding of the vaginal bacterial microbiota, mainly regarding areas relevant to clinicians specializing in vulvovaginal disorders.

MATERIALS AND METHODS

A search of PubMed database was performed, using the search terms "vaginal microbiome" with "Candida," "vaginitis," "urinary microbiome," "recurrent urinary tract infections," "sexually transmitted infections," "human immunodeficiency virus," "human papillomavirus," "nonspecific vaginitis," "vulvodynia," and "vulvovaginal symptoms." Full article texts were reviewed. Reference lists were screened for additional articles. The third article in this series describes VMB in various urogenital disorders.

RESULTS

Variable patterns of the VMB are found in patients with vulvovaginal candidiasis, challenging the idea of a protective role of lactobacilli. Highly similar strains of health-associated commensal bacteria are shared in both the bladder and vagina of the same individual and may provide protection against urinary tract infections. Dysbiotic VMB increases the risk of urinary tract infection. Loss of vaginal lactic acid-producing bacteria combined with elevated pH, increase the risk for sexually transmitted infections, although the exact protective mechanisms of the VMB against sexually transmitted infections are still unknown.

CONCLUSIONS

The VMB may constitute a biological barrier to pathogenic microorganisms. When the predominance of lactobacilli community is disrupted, there is an increased risk for the acquisition of various vaginal pathogents. Longitudinal studies are needed to describe the association between the host, bacterial, and fungal components of the VMB.

Bacterial vaginosis in pregnancy - a storm in the cup of tea

Human vaginal microbiota is dominated by Lactobacillus spp both in the non-pregnant and pregnant state. Bacterial vaginosis (BV) is an imbalance of vaginal microbiota caused by a reduction in the normal lactobacillary bacteria, and a heavy over-growth of mixed anaerobic bacteria. Various clinical (Amsel's Criteria), laboratory (Nugent's score) and molecular diagnostic method (quantitative PCR) are used for diagnosis. BV in pregnancy is associated with increased risk of preterm birth, low birth weight, chorioamnionitis and postpartum endometritis, apart from bothersome vaginal discharge. Antibiotic treatment with metronidazole or clindamycin are effective in eradicating bacterial vaginosis and safe to use in pregnancy. Treatment of bacterial vaginosis has not been shown to improve obstetric outcomes in women at low risk of preterm birth, but may reduce the risk of preterm birth and low birth weight in women at increased risk of preterm birth. Routine screening and treatment is not recommended in low risk women. Test for cure should be performed after treatment. Further research is required on other treatment modalities such as probiotic therapy and microbiota transplantation.

Regular use of depot medroxyprogesterone acetate causes thinning of the superficial lining and apical distribution of HIV target cells in the human ectocervix

BACKGROUND

The hormonal contraceptive depot medroxyprogesterone acetate (DMPA) may be associated with an increased risk of acquiring human immunodeficiency virus (HIV). We hypothesize that DMPA use influences the ectocervical tissue architecture and HIV target cell localization.

METHODS

Quantitative image analysis workflows were developed to assess ectocervical tissue samples collected from DMPA users and control subjects not using hormonal contraception.

RESULTS

Compared to controls, the DMPA group exhibited a significantly thinner apical ectocervical epithelial layer and a higher proportion of CD4+CCR5+ cells with a more superficial location. This localization corresponded to an area with a non-intact E-cadherin net structure. CD4+Langerin+ cells were also more superficially located in the DMPA group, while fewer in number compared to the controls. Natural plasma progesterone levels did not correlate with any of these parameters, whereas estradiol levels were positively correlated with E-cadherin expression and a more basal location for HIV target cells of the control group.

CONCLUSIONS

DMPA users have a less robust epithelial layer and a more apical distribution of HIV target cells in the human ectocervix, which could confer a higher risk of HIV infection. Our results highlight the importance of assessing intact genital tissue samples to gain insights into HIV susceptibility factors.

Vaginal Microbiota Evaluation and Lactobacilli Quantification by qPCR in Pregnant and Non-pregnant Women: A Pilot Study

Pregnancy outcomes and women's health are directly affected by vaginal microbiota. This microbiota consists of a dynamic ecosystem of various microbes in different ratios, which in healthy conditions protect the vaginal epithelium from infections. However, cases of vaginal infection are regularly diagnosed in women of reproductive age, contributing to more severe outcomes. Therefore, our main goal was to determine the prevalence of bacterial vaginosis (BV), aerobic vaginitis (AV), and vulvovaginal candidiasis (VVC) among Ecuadorian pregnant and non-pregnant women. A cross-sectional study was conducted among 217 women between 13 and 40 years old seeking primary healthcare in Carlos Andrade Marin Hospital (HCAM), Gynecological-Obstetric Hospital Isidro Ayora (HGOIA) and Center for Teaching Health Cipriana Dueñas during October 2018 to February 2019. The classical characterization of the vaginal microbiota was performed through microscopy by the Nugent criteria to evaluate the presence of BV, healthy and intermediate microbiota, by the criteria of Donders to determine the presence of AV and by the Marot-Leblond criteria to diagnose VVC. DNA extraction from vaginal samples and Polymerase Chain Reaction (PCR) analysis was performed to characterize the presence of Gardnerella spp., Mobiluncus mulieris, Escherichia coli, Enterococcus spp., and Lactobacillus spp. Finally, quantification of the lactobacilli was performed by quantitative real-time PCR (qPCR) for samples from women with normal vaginal microbiota and women with AV. Our results showed 52% of women with healthy microbiota, 7% with intermediate microbiota, and 41% with vaginal dysbiosis, comprising 27% with AV, 8% with BV and 4% with VVC and 2% with co-infections or co-dysbiosis. Additionally, a higher amount of lactobacilli were found in pregnant women when compared to non-pregnant women, while AV cases were characterized by a significant drop of Lactobacillus spp., more precisely, between 1E3 and 1E5 colony forming units (CFU)/ml. Finally, women with normal vaginal microbiota showed an average load of lactobacilli between 1E6 and 1E7 CFU/ml. This pilot study showed no statistically significant differences between pregnant and non-pregnant women, pointing to the possibility to use lactobacilli quantification for the prevention of future vaginal infections.

The genital tract and rectal microbiomes: their role in HIV susceptibility and prevention in women

INTRODUCTION

Young women in sub-Saharan Africa are disproportionately affected by HIV, accounting for 25% of all new infections in 2017. Several behavioural and biological factors are known to impact a young woman's vulnerability for acquiring HIV. One key, but lesser understood, biological factor impacting vulnerability is the vaginal microbiome. This review describes the vaginal microbiome and examines its alterations, its influence on HIV acquisition as well as the efficacy of HIV prevention technologies, the role of the rectal microbiome in HIV acquisition, advances in technologies to study the microbiome and some future research directions.

DISCUSSION

Although the composition of each woman's vaginal microbiome is unique, a microbiome dominated by Lactobacillus species is generally associated with a "healthy" vagina. Disturbances in the vaginal microbiota, characterized by a shift from a low-diversity, Lactobacillus-dominant state to a high-diversity non-Lactobacillus-dominant state, have been shown to be associated with a range of adverse reproductive health outcomes, including increasing the risk of genital inflammation and HIV acquisition. Gardnerella vaginalis and Prevotella bivia have been shown to contribute to both HIV risk and genital inflammation. In addition to impacting HIV risk, the composition of the vaginal microbiome affects the vaginal concentrations of some antiretroviral drugs, particularly those administered intravaginally, and thereby their efficacy as pre-exposure prophylaxis (PrEP) for HIV prevention. Although the role of rectal microbiota in HIV acquisition in women is less well understood, the composition of this compartment's microbiome, particularly the presence of species of bacteria from the Prevotellaceae family likely contribute to HIV acquisition. Advances in technologies have facilitated the study of the genital microbiome's structure and function. While next-generation sequencing advanced knowledge of the diversity and complexity of the vaginal microbiome, the emerging field of metaproteomics, which provides important information on vaginal bacterial community structure, diversity and function, is further shedding light on functionality of the vaginal microbiome and its relationship with bacterial vaginosis (BV), as well as antiretroviral PrEP efficacy.

CONCLUSIONS

A better understanding of the composition, structure and function of the microbiome is needed to identify opportunities to alter the vaginal microbiome and prevent BV and reduce the risk of HIV acquisition.

Hormonal Contraception and HIV-1 Acquisition: Biological Mechanisms

Access to effective affordable contraception is critical for individual and public health. A wide range of hormonal contraceptives (HCs), which differ in composition, concentration of the progestin component, frequency of dosage, and method of administration, is currently available globally. However, the options are rather limited in settings with restricted economic resources that frequently overlap with areas of high HIV-1 prevalence. The predominant contraceptive used in sub-Saharan Africa is the progestin-only three-monthly injectable depot medroxyprogesterone acetate. Determination of whether HCs affect HIV-1 acquisition has been hampered by behavioral differences potentially confounding clinical observational data. Meta-analysis of these studies shows a significant association between depot medroxyprogesterone acetate use and increased risk of HIV-1 acquisition, raising important concerns. No association was found for combined oral contraceptives containing levonorgestrel, nor for the two-monthly injectable contraceptive norethisterone enanthate, although data for norethisterone enanthate are limited. Susceptibility to HIV-1 and other sexually transmitted infections may, however, be dependent on the type of progestin present in the formulation. Several underlying biological mechanisms that may mediate the effect of HCs on HIV-1 and other sexually transmitted infection acquisition have been identified in clinical, animal, and ex vivo studies. A substantial gap exists in the translation of basic research into clinical practice and public health policy. To bridge this gap, we review the current knowledge of underlying mechanisms and biological effects of commonly used progestins. The review sheds light on issues critical for an informed choice of progestins for the identification of safe, effective, acceptable, and affordable contraceptive methods.

A role for the endometrial microbiome in dysfunctional menstrual bleeding

This study aimed to characterise the microbial community within the endometrial cavity and endocervix in women with menorrhagia or dysmenorrhea. Paired endocervical and endometrial biopsy samples were collected from women undergoing operative hysteroscopy and/or laparoscopy. Samples were cohorted based on pathology, indications for surgery, and histological dating of the endometrium. Samples were interrogated for the presence of microbial DNA using a two-step next generation sequencing technology approach to exploit the V5-V8 regions of the 16S rRNA gene. Pyrosequencing revealed that the endocervix and endometrium share a minor microbial community, but that each site harbours a separate and distinct microbial population (p = 0.024). This was also the case for women with menorrhagia and dysmenorrhea (p = 0.017). Lactobacillus spp. were the most abundant microbial taxa present in 50% of the cohorts, and across all endocervical groups. Members of the genera Prevotella, Fusobacterium and Jonquetella were the most abundant taxa identified in samples collected from nulliparous women. It can be concluded that the female upper genital tract is not sterile. Microbial community profiling revealed differences in the endometrial microbial community profiles for: (1) the endocervix compared to the endometrium, and (2), women with menorrhagia versus dysmenorrhea. The distinct microbial community profiles in these women may offer insight into the pathology and clinical management of dysfunctional menstrual bleeding.

Psychosocial Stress, Cortisol Levels, and Maintenance of Vaginal Health

Stress stimuli are ubiquitous and women do not enjoy any exemptions. The physiologic "fight-or-flight" response may be deleterious to the female lower genital tract microbiome if the stress stimuli persist for longer than necessary. Persistent exposure to psychosocial stress and stimulation of the hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenal-medullary (SAM) axes, and associated hormones are risk factors for several infections including genitourinary tract infections. Though this could be due to a dysregulated immune response, a cortisol-induced inhibition of vaginal glycogen deposition may be involved especially in the instance of vaginal infection. The estrogen-related increased vaginal glycogen and epithelial maturation are required for the maintenance of a healthy vaginal ecosystem (eubiosis). The ability of cortisol to disrupt this process as indicated in animal models is important in the pathogenesis of vaginal dysbiosis and the subsequent development of infection and inflammation. This phenomenon may be more crucial in pregnancy where a healthy Lactobacillus-dominated vaginal microbiota is sacrosanct, and there is local production of more corticotropin-releasing hormone (CRH) from the decidua, fetal membranes and placenta. To highlight the relationship between the stress hormone cortisol and the vaginal microbiomial architecture and function, the potential role of cortisol in the maintenance of vaginal health is examined.

The Vaginal Microbiota and Urinary Tract Infection

The vagina is a key anatomical site in the pathogenesis of urinary tract infection (UTI) in women, serving as a potential reservoir for infecting bacteria and a site at which interventions may decrease the risk of UTI. The vaginal microbiota is a dynamic and often critical factor in this pathogenic interplay, because changes in the characteristics of the vaginal microbiota resulting in the loss of normally protective Lactobacillus spp. increase the risk of UTI. These alterations may result from the influence of estrogen deficiency, antimicrobial therapy, contraceptives, or other causes. Interventions to reduce adverse effects on the vaginal microbiota and/or to restore protective lactobacilli may reduce the risks of UTI.

Hydrogen Peroxide-Producing Lactobacilli Are Associated With Lower Levels of Vaginal Interleukin-1β, Independent of Bacterial Vaginosis

BACKGROUND

The presence of hydrogen peroxide (H2O2)-producing lactobacilli in the vagina is associated with decreased rates of preterm birth and HIV acquisition. We hypothesize that this is due to immunomodulatory effects of these species.

METHODS

Concentrations of interleukin (IL)-1β, IL-6, IL-8, secretory leukocyte protease inhibitor, and human β-defensin 2 were quantified from vaginal swabs from 4 groups of women: women with and without bacterial vaginosis (BV) by Nugent score, further stratified by detection of H2O2-producing lactobacilli by semiquantitative culture. Ten quantitative polymerase chain reaction assays characterized the presence and quantity of select Lactobacillus and BV-associated species in each group. Levels of immune markers and bacteria were compared between the 4 groups using analysis of variance, Kruskal-Wallis, Mann-Whitney U, or χ tests.

RESULTS

Swabs from 110 women from 4 groups were included: 26 had a normal Nugent score (BV-), and no H2O2-producing lactobacilli detected (H2O2-); 47 were BV-, H2O2+; 27 BV+, H2O2-; and 10 BV+, H2O2+. The groups were similar in age, marital status, and reproductive history, but not ethnicity: the BV-, H2O2- group had more white participants (P = 0.02). In women with and without BV, IL-1β was lower in the H2O2+ groups. Human β-defensin 2 was lowest in BV+ H2O2- women and highest in BV-, H2O2-. Secretory leukocyte protease inhibitor was lower in women with BV and did not differ by the presence of H2O2-producing lactobacilli. In regression analysis, higher quantities of Lactobacillus crispatus were associated with lower quantities of IL-1β. Detection and quantity of BV-associated species by quantitative polymerase chain reaction was significantly different between women with and without BV, but not between women with and without H2O2-producing lactobacilli within those groups.

CONCLUSIONS

The presence of H2O2-producing lactobacilli is associated with lower levels of some vaginal proinflammatory cytokines, even in women with BV.

Normal Vulvovaginal Health in Adolescents

As adolescence is often the first time a woman will see a gynecologist, it is important for health care providers to understand and be capable of explaining the changes that occur to a young woman during these years. Many adolescents and their caretakers who seek gynecologic care for what they consider vulvovaginal abnormalities may be misinterpreting completely normal changes; education and reassurance are the best treatment in these cases. Most medical literature on vulvovaginal health focuses on abnormalities and there is a paucity of information on what is considered "normal." This goal of this review is to describe normal anatomic and physiologic vulvovaginal changes that occur during the adolescent years, as well as to offer advice on how to educate and reassure young women during this vulnerable time.

Progesterone-based intrauterine device use is associated with a thinner apical layer of the human ectocervical epithelium and a lower ZO-1 mRNA expression

Currently, whether hormonal contraceptives affect male to female human immunodeficiency virus (HIV) transmission is being debated. In this study, we investigated whether the use of progesterone-based intrauterine devices (pIUDs) is associated with a thinning effect on the ectocervical squamous epithelium, down-regulation of epithelial junction proteins, and/or alteration of HIV target cell distribution in the human ectocervix. Ectocervical tissue biopsies from healthy premenopausal volunteers using pIUDs were collected and compared to biopsies obtained from two control groups, namely women using combined oral contraceptives (COCs) or who do not use hormonal contraceptives. In situ staining and image analysis were used to measure epithelial thickness and the presence of HIV receptors in tissue biopsies. Messenger RNA levels of epithelial junction markers were measured by quantitative PCR. The epithelial thickness displayed by women in the pIUD group was similar to those in the COC group, but significantly thinner as compared to women in the no hormonal contraceptive group. The thinner epithelial layer of the pIUD group was specific to the apical layer of the ectocervix. Furthermore, the pIUD group expressed significantly lower levels of the tight junction marker ZO-1 within the epithelium as compared to the COC group. Similar expression levels of HIV receptors and coreceptors CD4, CCR5, DC-SIGN, and Langerin were observed in the three study groups. Thus, women using pIUD displayed a thinner apical layer of the ectocervical epithelium and reduced ZO-1 expression as compared to control groups. These data suggest that pIUD use may weaken the ectocervical epithelial barrier against invading pathogens, including HIV.

A combined oral contraceptive affects mucosal SHIV susceptibility factors in a pigtail macaque (Macaca nemestrina) model

BACKGROUND

Injectable hormonal contraception may increase women's risk of HIV acquisition and can affect biological risk factors in animal models of HIV. We established, for the first time, a model to investigate whether combined oral contraceptives (COC) alter SHIV susceptibility in macaques.

METHODS

Seven pigtail macaques were administered a monophasic levonorgestrel (LNG)/ethinyl estradiol (EE) COC at 33% or 66% of the human dose for 60 days. Menstrual cycling, vaginal epithelial thickness, and other SHIV susceptibility factors were monitored for a mean of 18 weeks.

RESULTS

Mean vaginal epithelial thicknesses were 290.8 μm at baseline and 186.2 μm during COC (P = 0.0141, Mann-Whitney U-test). Vaginal pH decreased from 8.5 during treatment to 6.5 post-treatment (0.0176 two-tailed t-test). Measured microflora was unchanged.

CONCLUSIONS

COC caused thinning of the vaginal epithelium and vaginal pH changes, which may increase SHIV susceptibility. 0.033 mg LNG + .0066 mg EE appeared effective in suppressing ovulation.

Effects of estroprogestins containing natural estrogen on vaginal flora

Estroprogestins with "natural oestrogen" has represented a new option in terms of combined hormonal contraception. So, the aim of this study is to investigate how estroprogestins with natural estrogen may modify the vaginal niche. In literature, very few studies focused on the interaction between hormonal contraception and vaginal milieu. This is a prospective comparative study. We enrolled 60 women from January 2013 to September 2013, 30 of them were administered estradiol valerate dienogest (E2V+DNG - Klaira®) in a quadriphasic regimen, while the other 30 women were administered 17-β estradiol with nomestrol acetate (EV+NOMAC - Zoely®) in a monophasic regimen. After a baseline study of vaginal milieu at recruitment of patients (Gram stain with Nugent score, vaginal pH, vaginal wet mount for the quantification of leukocytes, Lactobacilli and/or presence of Candida), we performed the same follow-up after six months of estroprogestin therapy. Our results showed that the women treated with E2V+DNG had a trend of an improvement of vaginal health in terms of increase of lactobacillar flora and reduction of vaginal pH in place of women treated with EV+NOMAC that showed a reduction of cervical mucus. Finally, our data about the effects on vaginal flora exerted by two estroprogestin pills (EPs) containing a natural estrogen suggest slight, but interesting differences in terms of vaginal ecology. These differences could be related to the type of estrogen, type of progestin, regimen of administration and, after all, to the net balance between estrogenic and progestin component of the EPs.

The structure of the human vaginal stratum corneum and its role in immune defense

The superficial layers of the human vaginal epithelium, which form an interface between host and environment, are comprised of dead flattened cells that have undergone a terminal cell differentiation program called cornification. This entails extrusion of nuclei and intercellular organelles, and the depletion of functional DNA and RNA precluding the synthesis of new proteins. As a consequence, the terminally differentiated cells do not maintain robust intercellular junctions and have a diminished capacity to actively respond to microbial exposure, yet the vaginal stratum corneum (SC) mounts an effective defense against invasive microbial infections. The vaginal SC in reproductive-aged women is comprised of loosely connected glycogen-filled cells, which are permeable to bacterial and viral microbes as well as molecular and cellular mediators of immune defense. We propose here that the vaginal SC provides a unique microenvironment that maintains vaginal health by fostering endogenous lactobacilli and retaining critical mediators of acquired and innate immunity. A better understanding of the molecular and physicochemical properties of the vaginal SC could promote the design of more effective topical drugs and microbicides.

Counseling on vaginal delivery of contraceptive hormones: implications for women's body knowledge and sexual health

BACKGROUND

Healthcare providers (HCPs) have an important role in helping women select the contraceptive method that best matches their needs and lifestyle. Recent surveys outline the need of women to be informed about all available choices, including the newest methods (particularly those not requiring daily administration), such as vaginal contraception.

METHODS

The most relevant publications on combined contraceptive vaginal ring are revised in the context of counseling as an opportunity to empower women in term of vaginal health and sexual functioning.

RESULTS

HCPs should explain the main characteristics of the combined contraceptive vaginal ring including the anatomical and physiological implications that make the vagina an ideal route of hormonal administration and the basic notions about functional modifications of the vagina during reproductive life. Clinical data on the vaginal ring should be summarized with regard to efficacy, tolerability, pharmacokinetics, cycle control and user acceptability, including recent findings on extra-contraceptive benefits (also compared to other hormonal contraceptives) on the vaginal flora and on sexual function.

CONCLUSION

Vaginal contraception offers various benefits and should always be discussed during contraceptive counseling. An open dialogue about vaginal contraception will also help enhance body knowledge and sexual health.

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

OBJECTIVE

A 2012 WHO consultation concluded that combined oral contraception (COC) does not increase HIV acquisition in women, but the evidence for depot medroxyprogesterone acetate (DMPA) is conflicting. We evaluated the effect of COC and DMPA use on the vaginal microbiome because current evidence suggests that any deviation from a 'healthy' vaginal microbiome increases women's susceptibility to HIV.

METHODS

We conducted a systematic review and reanalysed the Hormonal Contraception and HIV Acquisition (HC-HIV) study. Vaginal microbiome outcomes included bacterial vaginosis by Nugent scoring, vaginal candidiasis by culture or KOH wet mount and microbiome compositions as characterized by molecular techniques.

RESULTS

Our review of 36 eligible studies found that COC and DMPA use reduce bacterial vaginosis by 10-20 and 18-30%, respectively. The HC-HIV data showed that COC and DMPA use also reduce intermediate microbiota (Nugent score of 4-6) by 11% each. In contrast, COC use (but not DMPA use) may increase vaginal candidiasis. Molecular vaginal microbiome studies (n=4) confirm that high oestrogen levels favour a vaginal microbiome composition dominated by 'healthy' Lactobacillus species; the effects of progesterone are less clear and not well studied.

CONCLUSION

DMPA use does not increase HIV risk by increasing bacterial vaginosis or vaginal candidiasis. COC use may predispose for vaginal candidiasis, but is not believed to be associated with increased HIV acquisition. However, the potential role of Candida species, and vaginal microbiome imbalances other than bacterial vaginosis or Candida species, in HIV transmission cannot yet be ruled out. Further in-depth molecular studies are needed.

Monitoring vaginal epithelial thickness changes noninvasively in sheep using optical coherence tomography

OBJECTIVE

High-resolution optical coherence tomography can be used noninvasively to evaluate vaginal morphologic features, including epithelial thickness, to assess this protective barrier in transmission of sexually transmitted infections and to monitor tissue response to topical medications and hormonal fluctuations. We examined the use of optical coherence tomography to measure epithelial thickness noninvasively before and after topical treatment with a drug that causes epithelial thinning.

STUDY DESIGN

Twelve female sheep were treated with intravaginal placebo (n = 4) or nonoxynol-9 (n = 8). Vaginal optical coherence tomography images were obtained before and 24 hours after treatment. Four sheep in the nonoxynol-9 group were also examined on days 3 and 7. Vaginal biopsies were obtained on the last examination day. Epithelial thickness was measured in optical coherence tomography images and in hematoxylin and eosin-stained histologic sections from biopsies. Statistical analysis was performed using analyses of variance (significance P < .05).

RESULTS

Baseline optical coherence tomography epithelial thickness measurements were similar (85 ± 19 μm placebo, 78 ± 20 μm nonoxynol-9; P = .52). Epithelial thinning was significant after nonoxynol-9 (32 ± 22 μm) compared with placebo (80 ± 15 μm) 24 hours after treatment (P < .0001). In the 4 nonoxynol-9-treated sheep followed for 7 days, epithelial thickness returned to baseline by day 3, and increased significantly on day 7. Epithelial thickness measurements from histology were not significantly different than optical coherence tomography (P = .98 nonoxynol-9, P = .93 hydroxyethyl cellulose).

CONCLUSION

Drug-induced changes in the epithelium were clearly detectable using optical coherence tomography imaging. Optical coherence tomography and histology epithelial thickness measurements were similar, validating optical coherence tomography as a noninvasive method for epithelial thickness measurement, providing an important tool for quantitative and longitudinal monitoring of vaginal epithelial changes.

Interaction between lactobacilli, bacterial vaginosis-associated bacteria, and HIV Type 1 RNA and DNA Genital shedding in U.S. and Kenyan women

Bacterial vaginosis has been associated with genital HIV-1 shedding; however, the effect of specific vaginal bacterial species has not been assessed. We tested cervicovaginal lavage from HIV-1-seropositive women for common Lactobacillus species: L. crispatus, L. jensenii, and seven BV-associated species: BVAB1, BVAB2, BVAB3, Leptotrichia, Sneathia, Megasphaera, and Atopobium spp. using quantitative PCR. We used linear and Poisson regression to evaluate associations between vaginal bacteria and genital HIV-1 RNA and DNA. Specimens from 54 U.S. (310 visits) and 50 Kenyan women (137 visits) were evaluated. Controlling for plasma viral load, U.S. and Kenyan women had similar rates of HIV-1 RNA (19% of visits vs. 24%; IRR=0.95; 95% CI 0.61, 1.49) and DNA shedding (79% vs. 76%; IRR=0.90; 0.78, 1.05). At visits during antiretroviral therapy (ART), the likelihood of detection of HIV-1 RNA shedding was greater with BVAB3 (IRR=3.16; 95% CI 1.36, 7.32), Leptotrichia, or Sneathia (IRR=2.13; 1.02, 4.72), and less with L. jensenii (IRR=0.39; 0.18, 0.84). At visits without ART, only L. crispatus was associated with a lower likelihood of HIV-1 RNA detection (IRR=0.6; 0.40, 0.91). Vaginal Lactobacillus species were associated with lower risk of genital HIV-1 shedding, while the presence of certain BV-associated species may increase that risk.

Effects of hormonal contraception on vaginal flora

BACKGROUND

The sector of the market that deals with contraception offers a long list of different contraceptive methods. Within the estroprogestinic choice, the routes of administration are oral, transdermic and vaginal one. Even though efficacy is comparable with these methods, secondary and adverse effects are directly involved in the acceptability of the method.

STUDY DESIGN

This was a prospective comparative study. During 1 year, we enrolled 60 asymptomatic women who voluntarily requested combined oral contraception (COC) or combined contraceptive vaginal ring (CCVR group). After a baseline study of vaginal milieu prior to starting hormonal contraception, we performed a follow-up. For each woman, we examined vaginal pH; quantification of leukocytes, lactobacilli, Candida and cocci on saline microscopy fluid; Gram stain with Nugent score and the presence of vaginal infection [culture for Trichomonas vaginalis, albicans and nonalbicans Candida, Group B Streptococcus (GBS)].

RESULTS

At the end of follow-up, there was a little change of vaginal milieu in both groups. We noted an increase of lactobacilli in the CCVR users and an increase of GBS in COC users.

CONCLUSION

CCVR compared to COC users showed an increase of the number of lactobacilli in vaginal flora. It means that an increase of leukorrhea in that group could be protective in terms of prevention of vaginal imbalance/infection.

Effect of sexual activity on vaginal colonization with hydrogen peroxide-producing lactobacilli and Gardnerella vaginalis

BACKGROUND

Bacterial vaginosis is associated with sexual activity, but mechanisms for this association are unclear.

STUDY DESIGN

Cross-sectional analysis of data from women reporting sex with women who provided information on sexual behaviors as part of a study of vaginal bacteria was conducted. Vaginal bacteria were detected by semiquantitative culture. Binomial regression with log-link evaluated associations between detection of bacteria and sexual behaviors reported to occur before enrollment. Linear regression evaluated associations between these behaviors and quantity of bacteria.

RESULTS

Of the 320 women, 216 (68%) were colonized with H2O2-producing lactobacilli and 142 (44%) with Gardnerella vaginalis. Colonization with G. vaginalis was associated with >20 digital-vaginal sex acts (risk ratio, 2.01; 1.22, 3.29) or >10 toy-vaginal acts in the past 3 months (risk ratio, 1.76; 1.32, 2.36). Quantity of H2O2-producing lactobacilli was 1.3 log lower in colonized women reporting >10 acts of insertive vaginal sex-toy use in the past 3 months (95% confidence interval: -2.04, -0.56), 1.19 log lower with toy-vaginal sex in past 7 days (-1.75, -0.62), and 0.78 log lower in women sharing toys with a partner (-1.25, -0.31).

CONCLUSIONS

Vaginal insertive use and sharing of sex toys were associated with decreased quantities of H2O2-producing lactobacilli and higher risk of colonization with G. vaginalis.

Dynamics of the Vaginal Ecosystem—Hormonal Influences

The vagina is a dynamic and finely tuned ecosystem in which homeostasis depends on mutually beneficial interactions between a human female and her resident microorganisms, an ecosystem that can be thrown off balance by a wide variety of both intrinsic and extrinsic factors. Although a functional equilibrium provides stability to the ecosystem considered crucial to maintaining vaginal health, “normal flora” is a concept currently being redefined. New methodologies enable molecular analyses of the vaginal microbiota which have widened the definition of “normal” from a single specific microbiological profile to a range of functional microbial equilibria dependent upon pertinent host and microbial factors. One of the strongest influences on the vaginal microbiota is the hormonal changes that define the reproductive phases of a woman's life. The vaginal environment is particularly responsive to estrogen, a hormone that creates distinctive changes in the vaginal microbiota. This review summarizes the components of a healthy vaginal ecosystem during the reproductive years, including the characteristics of a healthy equilibrium and factors that can disturb a functional balance. It also summarizes what is known about the vaginal microbiota in childhood and after menopause. Healthful ecosystems at any stage of a female's reproductive life will be characterized by a microbiota that both maintains physiological function and though changeable, adapts to normal perturbation without succumbing to disease.

The vulval vestibular mucosa?morphological effects of oral contraceptives and menstrual cycle

BACKGROUND

An erythematous and hypersensitive vestibular mucosa has been observed during the use of combined oral contraceptives (COC). Hormonal effects on the vestibular morphology have not been studied.

OBJECTIVES

Our aim was to evaluate the morphology of the vulval vestibular mucosa during the influence of COC and during the menstrual cycle.

METHODS

Forty-five healthy women (20 using COC and 25 not using COC) were included. A 6-mm punch biopsy was obtained from the right posterior vestibule on days 7-11 of the menstrual cycle. A corresponding biopsy was taken 2 weeks later in 16 women without COC. The epithelial morphology was estimated by measuring interdermal papilla distance, dermal papilla to surface, from basal layer to surface and width of dermal papillae. A histopathological assessment was made.

RESULTS

The vulval vestibular mucosa of women using COC displayed a larger distance between the dermal papillae (P = 0.04) and a larger space from the dermal papillae to the epithelial surface (P = 0.03) compared with controls in the follicular phase. Women without COC displayed a larger interdermal papilla distance in the luteal phase compared with the follicular phase, P = 0.02. Histopathology showed more superficial blood vessels in the COC users (P < 0.01).

CONCLUSIONS

The vulval vestibular mucosa of women with COC display an altered morphological pattern with shallow and sparse dermal papillae compared with the follicular phase. Similar findings are seen in women without COC during the luteal phase which indicate a gestagenic effect on the mucosa. Associations between the morphological pattern and changes in mucosal mechanical sensitivity require further studies.

Safety, tolerance and acceptability of the Invisible Condom® and its vaginal applicator in healthy women and their male sexual partners

OBJECTIVES

The study was conducted to evaluate the safety and acceptability of the Invisible Condom when applied once or twice daily for 14 days in healthy women and their male sexual partners.

STUDY DESIGN

Forty-one women and 23 men divided into three cohorts were enrolled. Cohort 1:14 sexually abstinent women applying gel twice daily for 14 days; Cohort 2:14 sexually active women with tubal ligation applying gel once daily for 14 days and their 14 sexual partners who did not use gel; Cohort 3:13 women on oral contraceptive applying gel once daily for 14 days and 9 of their sexual partners.

RESULTS

No serious adverse events (AEs) were reported. Colposcopy showed no genital ulceration nor epithelial lesions. No major changes in vaginal flora or vaginal pH were detected. None of the women had to stop product application because of AEs. The majority of AEs were mild. Common AEs were itching, dryness, burning sensation, erythema and discharge. Satisfaction questionnaire showed that the gel and applicator were acceptable.

CONCLUSION

The Invisible Condom and applicator were safe, well tolerated and acceptable when applied intravaginally for 14 days. Thus, expanded safety and effectiveness evaluation is warranted.

Ecological effects of perorally administered pivmecillinam on the normal vaginal microflora

The knowledge of the effects of antimicrobial agents on the normal vaginal microflora is limited. The objective of the present study was to study the ecological impact of pivmecillinam on the normal vaginal microflora. In 20 healthy women, the estimated day of ovulation was determined during three subsequent menstrual cycles. Microbiological and clinical examinations were performed on the estimated day of ovulation and on day 3 in all cycles and also on day 7 after ovulation in cycles 1 and 2. Anaerobic and facultative anaerobic gram-positive rods, mainly species of lactobacilli and actinomycetes, dominated the microflora. One woman was colonized on the third day of administration with a resistant Escherichia coli strain, and Candida albicans was detected in one woman on days 3 and 7 in cycle 2. No other major changes in the normal microflora occurred during the study. Administration of pivmecillinam had a minor ecological impact on the normal vaginal microflora.

Vaginal Yeast Colonization in Nonpregnant Women: A Longitudinal Study

OBJECTIVE

We sought to investigate the prevalence and risk factors for vaginal yeast colonization over a 1-year period.

METHODS

We conducted a longitudinal cohort study of 1,248 asymptomatic young women by collecting demographic and behavioral data at baseline, 4, 8, and 12 months.

RESULTS

Seventy percent of women were colonized by vaginal yeast at one or more visits, but only 4% were colonized at all 4 visits. Using an adjusted generalized estimating equation model, factors associated with vaginal yeast colonization were marijuana use in the previous 4 months, depomedroxyprogesterone acetate use in the past 4 months, sexual intercourse in the previous 5 days, and concurrent colonization with lactobacilli and group B streptococcus. Symptoms of pruritus and vulvovaginal burning were associated with yeast colonization, but antifungal use was not.

CONCLUSION

Recent sexual intercourse and use of injection contraceptives are risk factors for yeast colonization. Rates of antifungal use did not show an association with yeast colonization. The reporting of antifungal use by women lacking yeast colonization suggests that self-diagnosis is inaccurate.

LEVEL OF EVIDENCE

II-2.

Site-specific prevalence and cell densities of selected microbes in the lower reproductive tract of menstruating tampon users

OBJECTIVE

To assess differences in prevalence and cell densities of enterococci, Gram negative enterics (GNEs), yeast and Staphylococcus aureus among four genital sites and to examine whether the presence of organisms at one site affected the presence of organisms at other sites.

METHODS

Swab samples from the perineum, below and above the hymen, and the posterior fornix obtained from 52 tampon users on menstrual cycle day 3 were analyzed for site-specific prevalence and cell densities of microorganisms.

RESULTS

Enterococci and GNEs were the most prevalent study organisms at all sites and decreased in prevalence from the perineum to the posterior fornix. Cell densities similarly decreased from below the hymen to the posterior fornix. Yeast were detected at the hymen only; S. aureus frequency was similarly low at all sites. Yeast and S. aureus site-specific cell densities were similar. The above- and below-hymen sites were similar in prevalence and cell density of organisms. An above-chance association existed between the presence of any study organism below the hymen and above the hymen and was strongest for GNEs.

CONCLUSIONS

The pattern of genital colonization with enterococci and GNEs reflects their likely gastrointestinal source. The absence of significant differences in the prevalence and cell densities of study microflora above and below the hymen combined with an above-chance association of the presence of microorganisms at these regions suggests that the regions above and below the hymen are not different with respect to the presence of the organisms evaluated in this study.