Recent Biomarker-Confirmed Unprotected Vaginal Sex, But Not Self-reported Unprotected Sex, Is Associated With Recurrent Bacterial Vaginosis

Abstract

Background Self-reported unprotected vaginal sex appears to increase risk of bacterial vaginosis (BV). However, the validity of self-reports is questionable, given their inconsistency with more objective measures of recent semen exposure such as detection of prostate specific antigen (PSA). We examined whether recent unprotected sex, as measured both by PSA detection on vaginal swabs and by self-report, was associated with increased BV recurrence. Methods We analyzed randomized trial data from non-pregnant, BV-positive adult women recruited from a sexually transmitted diseases clinic. Participants received BV therapy at enrollment and were scheduled to return after 4, 12, and 24 weeks. BV (by Nugent score) and PSA were measured at each visit. We used Cox proportional hazards models to examine the association between PSA positivity and recurrent BV. We also evaluated associations between self-reported unprotected sex (ever/never since the last visit and in the last 48 hours, analyzed separately) and recurrent BV. Results PSA and BV results were available for 96 women who contributed 226 follow-up visits. PSA positivity was associated with increased BV recurrence (adjusted hazard ratio (aHR): 2.32, 95% confidence interval (CI): 1.28–4.21). In contrast, we observed no significant increase in BV recurrence among women self-reporting unprotected sex since the last visit (aHR: 1.63, 95% CI: 0.77–3.43) or in the last 48 hours (aHR: 1.28, 95% CI: 0.70–2.36). Conclusions Estimates from earlier studies linking self-reported unprotected sex and BV may be biased by misclassification. Biomarkers can improve measurement of unprotected sex, a critical exposure variable in sexual health research.

Detection of ureaplasmas and bacterial vaginosis associated bacteria and their association with non-gonococcal urethritis in men

“…It could be speculated that the presence of ureaplasmas resulted in an elevated pH due to the release of ammonia from urea hydrolysis, the main energy-generating mechanism used in ureaplasmas. Similar to the suggestions that alkalinisation of vaginal fluid by menstruation and semen increases the growth of BV associated microbiota [35], the same pH change elicited by ureaplasmas in the urethra where an abundance of urea is available, could play a role. As the correlation between ureaplasma and BV associated bacteria was found unexpectedly a long time after sample collection, pH measurements of the urethral secretions were not possible.…”

Prevalencia de vaginosis bacteriana y factores asociados en veinte ciudades del Perú

“…Esto se podría deber a que el semen contribuye a la eliminación de FVN y al desarrollo de VB (21,22) . La literatura reporta que casi el 50% de mujeres que tienen VB presentan síntomas (10) .…”

Vaginal Microbiome and Its Relationship to Behavior, Sexual Health, and Sexually Transmitted Diseases

“…30 Multiple, new, or increased number of male partners are strongly associated with bacterial vaginosis in multiple studies. 34,44 Recent unprotected sex as evidenced by the presence of prostate-specific antigen in vaginal fluid has been associated with a more than twofold increased risk of bacterial vaginosis 47 and recurrent bacterial vaginosis 48 and is negatively associated with the presence and concentration of healthy Lactobacillus species. 34 Additionally, there is a significant association between bacterial vaginosis and female sex partners, 29 because women who have sex with women appear to be at increased risk when compared with women who have sex with men only.…”