Associations between sexual habits, menstrual hygiene practices, demographics and the vaginal microbiome as revealed by Bayesian network analysis

Abstract

20The vaginal microbiome plays an influential role in several disease states in reproductive age 21 women, including bacterial vaginosis (BV). While demographic characteristics are associated 22 with differences in vaginal microbiome community structure, little is known about the influence 23 of sexual and hygiene habits. Furthermore, associations between the vaginal microbiome and risk 24 symptoms of bacterial vaginosis have not been fully elucidated. Using Bayesian network (BN) 25 analysis of 16S rRNA gene sequence results, demographic and extensive questionnaire data, we 26 describe both novel and previously documented associations between habits of women and their 27 vaginal microbiome. The BN analysis approach shows promise in uncovering complex 28 associations between disparate data types. Our findings based on this approach support published 29 associations between specific microbiome members (e.g., Eggerthella, Gardnerella, Dialister, 30 . CC-BY-NC-ND 4.0 International license It is made available under a was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. indicating that the Nugent Score may not be the most useful criteria for assessment of clinical 36 BV. We also found that demographics (i.e., age, ethnicity, previous pregnancy) were associated 37 with the presence/absence of specific vaginal microbes. The resulting BN revealed several as-yet 38 undocumented associations between birth control usage, menstrual hygiene practices and 39 specific microbiome members. Many of these complex relationships were not identified using 40 common analytical methods, i.e., ordination and PERMANOVA. While these associations 41 require confirmatory follow-up study, our findings strongly suggest that future studies of the 42 vaginal microbiome and vaginal pathologies should include detailed surveys of participants' 43 sanitary, sexual and birth control habits, as these can act as confounders in the relationship 44 between the microbiome and disease. Although the BN approach is powerful in revealing 45 complex associations within multidimensional datasets, the need in some cases to discretize the 46 data for use in BN analysis can result in loss of information. Future research is required to 47 alleviate such limitations in constructing BN networks. Large sample sizes are also required in 48 order to allow for the incorporation of a large number of variables (nodes) into the BN, 49 particularly when studying associations between metadata and the microbiome. We believe that 50 this approach is of great value, complementing other methods, to further our understanding of 51 complex associations characteristic of microbiome research. 52 53. CC-BY-NC-ND 4.0 International license It is made available under a was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.

The vaginal microbiota associates with the regression of untreated cervical intraepithelial neoplasia 2 lesions

“…hormonal changes associated with menses) and exogenous factors (e.g. contraception, sexual intercourse, hygiene practices) [24][25][26] . It is therefore striking that VMB composition at baseline associates with CIN2 regression or nonregression 12 and 24 months later, suggesting long-term interaction between vaginal bacterial composition and CIN2 natural history, however further studies on more densely sampled women would be required to elucidate this further.…”

Vaginal microbiota evaluation and prevalence of key pathogens in ecuadorian women: an epidemiologic analysis

“…Associations between the microbiota plus background variables and clinical outcomes in different stages of a woman’s life are complex, and which intrinsic or external factors drive the community composition it is not fully understood 61 , 62 . Behavioral factors, such as sexual behavior and methods of birth control, may contribute to lactobacilli reduction and leading to an intermediate microbiota or even a vaginal infection 54 , 63 – 65 . The present study showed the results of the vaginal microbiota colonization in Ecuadorian women from Pichincha province (considered as another ethnicity factor), after controlling the confounding factors, such as sociodemographic, behavioral or environmental variables.…”

Deciphering the effect of reproductive tract microbiota on human reproduction

“…These changes are associated with shifts in vaginal bacterial content, with menses representing the phase in which the microbiome is more diverse, while the oestradiol and progesterone peaks are more bacterially stable times . Some external factors can also modulate the vaginal microbiota, such as hygiene habits, sexual exposure, change of sexual partners, and use and type contraceptives . The factors influencing the structure and composition of the cervicovaginal microbiota were recently reviewed by Kroon and colleagues (Figure ) …”