While several different vaginal microbiota (VMB) community types have been identified, communities dominated by Lactobacillus confer colonization resistance to the vagina, and thus protect against bacterial vaginosis, STI, and other urogenital infectious diseases. Conversely, mixed communities that often include Gardnerella vaginalis and relatively few Lactobacillus spp. are considered unhealthy states and may contribute to bacterial vaginosis and various sequelae including infertility, endometriosis, pelvic inflammatory disease, and increased risk of STI. Considering the relationship between the vaginal microbiota and reproductive health, and the high prevalence of tampon use, it is surprising how few studies have examined the effect of tampon use on VMB composition. The majority of these studies are limited by the use of culture-dependent methods focused on the presence/absence of a small number of species. The one study to date that used culture-independent community analysis to answer this question is limited by its sample size of 7 women, and by its design in that vaginal swabs were only collected at two points during each menstrual cycle. Moreover, these studies’ conflicting findings mean that consensus on this topic has not been reached. The present study is a longitudinal, case-crossover study examining the impact of tampon use on the composition of the VMB multiple menstrual cycles. 21 women self-collected vaginal swabs twice a week for a post-menses baseline window of 2-3 weeks followed by three full menstrual cycles. During the first two menstrual cycles, women used study-assigned tampons and during the third cycle, they used tampons according to their normal practices. The vaginal swabs will be used to assess the VMB composition at each collection time point. We hypothesize that the degree of VMB composition change that occurs across each menses will depend on the immediately pre-menses VMB community type with less change occurring in Lactobacillus-dominated communities. We also hypothesize that the persistence of the VMB composition change that occurs across each menses will depend on the immediately pre-menses VMB community type with changes persisting longer between menses in diverse, non-Lactobacillus-dominated communities.
Sponsored by the Host Microbiome Initiative