Impact of surgical field disinfection on vaginal microbiome in transvaginal urogynecological surgery: a prospective cohort study

Abstract

Background: The study aimed to assess the effects of vaginal disinfection and sterile draping on the composition and dynamics of the vaginal microbiota during vaginal surgery.

Methods: A prospective cohort study was conducted involving post-menopausal patients undergoing vaginal urogynecological surgery. The vaginal microbiota was assessed by partial 16 S rRNA gene sequencing at three time points: before disinfection (V1); immediately after disinfection and sterile draping (V2); and one-hour post-disinfection (V3).

Findings: In a cohort of 54 postmenopausal women (median age: 69.2 ± 7.6 years), with a mean operative time of 92.89 ± 45.92 min, native tissue prolapse repair was the most common urogynecological vaginal procedure performed (n = 47, 87%). The vaginal microbiota diversity was significantly increased after disinfection associated with reduced abundance of Lactobacillus and Bifidobacterium and increased Pseudomonas (p < 0.0001). Community state type (CST) I prevalence decreased notably from 20% at V1 to 6% at V3, primarily due to the disappearance of CST I-A, while CST IV prevalence rose from 31 to 44%, which was mainly secondary to an increase in CST IV-C (from 20 to 33%).

Conclusions: These findings highlight the impact of povidone-iodine on vaginal microbiota composition during vaginal urogynecological surgery. Disinfection significantly increased vaginal bacterial diversity and reducing Lactobacillus abundance. This observation requires further exploration in the context of development of optimized disinfection protocols aimed at preserving vaginal health during and after surgery.

Keywords: Lactobacillus; Pseudomonas; CSTs; Disinfection; Povidone-iodine; Urogynecology; Vaginal microbiota diversity; Vaginal surgery.

Fig. 1

Longitudinal changes in vaginal microbial alpha diversity before disinfection (V1), after disinfection (V2), and one hour after disinfection (V3). (A) Comparison between (V1) and (V2). (B) Comparison between post-disinfection (V2) and 1-hour postoperative (V3). (C) Comparison between preoperative (V1) and 1-hour postoperative (V3). A significant modification was observed at V2 (p = 0.0014), and (V2) vs. (V3) (p < 0.00001), as well as between (V1) and (V3) (p = 0.00001)

Fig. 2

Principal Coordinates Analysis (PCoA) based on Bray–Curtis dissimilarity illustrating shifts in vaginal microbiota composition across three time points. Each point represents the microbial community of a single subject. Colored ellipses denote 95% confidence intervals for each visit group. Percentage values on axes represent the proportion of variance explained by the respective principal coordinate. Each color corresponds to a visit: red for V1, blue for V2, and green for V3

Fig. 3

Stacked bar plots showing the relative abundance of vaginal microbiota across three time points (V1, V2, and V3). Each bar represents the microbial composition of an individual participant using different colors to represent different phylum, genus, and species while the vertical axis represents their relative abundance. The Mann-Whitney test was used to compare relative abundance. (A) Microbial diversity at phylum level. (B) Microbial diversity at genus level. (C) Microbial diversity at species level

Fig. 4

Sankey diagram illustrating the longitudinal transitions of vaginal Community State Types (CSTs) and their subclasses across the three assessment timepoints (V1, V2, and V3). CST subclasses include I-A, I-B, II, III-A, III-B, IV-A, IV-B, and IV-C0 to IV-C4, defined based on Lactobacillus species dominance. Each stream represents a group of individuals sharing the same CST subclass at each visit and visualizes their progression or shift to other CST subclasses over time. A major transition is observed between V1, V2, and V3 where CST V completely disappeared at V2 and V3 while there was a high transition to CST IV