Targeting the vaginal microbiota with probiotics as a means to counteract infections

The microbial composition of the vagina of healthy and infected women is becoming more fully elucidated with molecular techniques. The purpose of this review is to examine our current understanding of the vaginal microbiota and assess how probiotic bacteria might reduce infectivity.

It appears that there are some remarkable similarities in the bacterial species that inhabit the vagina of women from diverse ethnic backgrounds. Yet, distinct outliers exist in which a small portion of apparently healthy women have extremely complex microbiota, whereas most have a relatively simple microbiota. Bacterial vaginosis is the most common aberrant condition in women, yet its pathogenesis is poorly understood and it is often asymptomatic. Vulvovaginal candidiasis is better known, yet many women self-treat with antifungals when in fact they have bacterial vaginosis. Urinary tract infection (UTI) remains extremely common, with no real breakthrough treatment or prevention strategy developed in the past 30 or more years. The ability of lactobacilli probiotic interventions to prevent, treat and improve the cure of these infections has long been considered and is now supported by some clinical evidence.

The mechanisms whereby certain probiotic lactobacilli improve urogenital health include immune modulation, pathogen displacement and creation of a niche less conducive to proliferation of pathogens and their virulence factors. Probiotics offer a potential new means to prevent urogenital infections and help maintain a healthy vaginal ecosystem.