Vestibulodynia and the Vaginal Microbiome: A Case-Control Study

Abstract

Background: Recent studies of the vaginal microbiome have led to a better understanding of the microbiota and interactions with the host environment, however the role of the vaginal microbiome in vestibulodynia remains unclear.

Aim: This study aims to investigate and examine differences in the bacterial and fungal microbiome among patients with vestibulodynia and healthy controls.

Methods: A case-control study was conducted examining the vaginal microbiome of 29 patients with vestibulodynia and 26 controls through Stony Brook University Obstetrics and Gynecology ambulatory clinic. Exclusion criteria included a diagnosis of vaginal infection at the time of presentation, a prior diagnosis of vulvodynia or receipt of treatment, immunosuppression, and receipt of steroid or antibiotic therapy. Vaginal swab samples were obtained from participants. DNA was extracted and sent for diversity assay of 16S rRNA for prokaryotic species and internal transcribed spacers (ITS) for fungi. Demographic characteristics for both cases and controls were obtained through a retrospective chart review.

Outcome measure: Principal component analysis (PCA) and linear discriminant analysis effect size (LefSe) were used to identify differences in relative abundance of operational taxonomic units (OTUs) for the vaginal microbiome between vestibulodynia patients and controls.

Results: Lactobacillus species were dominant amongst both cases and controls. PCA of 16S and ITS OTUs did not show significant differences in microbiome composition between vestibulodynia patients and controls. LefSe demonstrated higher abundance of Bifidobacterium longum, the Genus Sneathia, and the Family Leptotrichiaceae, in controls compared to vestibulodynia samples. For ITS, Aspergillus spp. was significantly more prevalent in controls than in vestibulodynia cases.

Clinical implications: Additional studies are needed to further assess the clinical significance of these findings.

Strengths and limitations: Strengths of this study include ITS amplicon sequence analysis for fungal species diversity. Limitations of this study include small sample size and lack of racial diversity.

Conclusions: Our study did not find significant differences in composition or diversity between the vaginal microbiomes of cases of vestibulodynia and controls; however, the data suggests differences in abundance of biota requiring further research for biological and clinical significance. Panzarella DA, Peresleni T, Collier JL, et al. Vestibulodynia and the Vaginal Microbiome: A Case-Control Study. J Sex Med 2022;19:1451-1462.

Keywords: Dyspareunia; Microbiome; Pain; Vestibulodynia; Vulvodynia.