(P470) Amsel-BV before and after a single exposure to lubricant during transvaginal ultrasound and incidence of Amsel-BV over 10 weeks compared to a lubricant-unexposed cohort

Background: Vaginal lubricant is commonly used during intercourse and procedures like transvaginal ultrasound (TVUS). Lubricants may increase risk for bacterial vaginosis (BV) due to high osmolality, and ingredients like glycols and chlorhexidine. We evaluated the association between Amsel-BV before and after lubricant use during TVUS, and Amsel-BV incidence compared to a cohort without recent lubricant use.

Methods: These secondary analyses utilized two non-pregnant, reproductive-age cohorts. Amsel-BV was defined by 3 of 4 clinical criteria (discharge, pH >4.5, Whiff+, clue cells). Lubricant-exposed participants were drawn from the Gynecology and Lubricants Effects study, which enrolled patients presenting for TVUS. Amsel-BV was assessed pre-TVUS at baseline (N=85), and post-TVUS (week 2, N=85; week 10, N=49). Lubricant-unexposed were drawn from a separate cohort at the University of Alabama Birmingham who reported no lubricant use 60 days prior to enrollment, and were evaluated for Amsel-BV at baseline, weeks 5 and 10 (N=43). First, McNemar’s test and logistic mixed effects models were used to evaluate paired and within-participant differences in asymptomatic or symptomatic Amsel-BV and individual Amsel’s criteria at week 2 post-TVUS (post-lubricant) versus pre-TVUS (pre-lubricant). Next, log-binomial regression was used to model the 10-week cumulative incidence of Amsel-BV comparing the lubricant-exposed and lubricant-unexposed cohorts. Participants with asymptomatic Amsel-BV at baseline, and antibiotic, antifungal, or commercial lubricant use before incident Amsel-BV were excluded.

Results: McNemar’s test found a participant was more likely to have Amsel-BV (p=0.03) and Whiff+ (p=0.02) at week 2 post-TVUS versus pre-TVUS. When the data were modeled, the odds of Amsel-BV and Whiff+ were 1.8-fold (95% CI:0.73-4.66) and 1.9-fold (95% CI:0.76-4.96) higher, respectively, week 2 post-TVUS versus pre-TVUS. Compared to the lubricant-unexposed cohort, the lubricant-exposed had a higher 10-week cumulative incidence of Amsel-BV (24% vs. 16%), but the model was not significant (aRR:1.34, 95% CI:0.56-3.17).

Conclusion: One-time lubricant exposure during TVUS was associated with more Amsel-BV and Whiff+ findings two weeks later in paired tests, but the association did not remain significant in logistic mixed effects models. Incidence of Amsel-BV was not significantly greater after one-time lubricant use compared to the lubricant-unexposed cohort. Larger studies with more frequent lubricant use may be needed to evaluate associations with BV.