Vaginal redox potential in bacterial vaginosis (nonspecific vaginitis).

To explore of the association of bacterial vaginosis with anaerobic bacterial growth in the vagina, we measured the redox potential (Eh) at the vaginal epithelial surface of women with this syndrome. Among normal women, the value for Eh in the vagina ranged from +322 mV to +137 mV (mean, +170 mV); whereas among women with bacterial vaginosis, the Eh ranged from +71 mV to as low as -257 mV (mean, -92 mV). Following successful treatment of the vaginosis with metronidazole, the vaginal Eh increased to a mean of +208 mV. Thus, the low redox potential in the vagina during bacterial vaginosis appears to be due to microbial metabolism in the vagina and does not represent a persistent host factor responsible for the anaerobic vaginal flora. Any host factors responsible for bacterial vaginosis remain to be elucidated.