Vaginal microflora associated with bacterial vaginosis in Japanese and Thai pregnant women

The vaginal flora of 118 Japanese and 208 Thai pregnant women were investigated for the presence of bacterial vaginosis (BV), BV-associated organisms, and BV-associated enzyme. A similar prevalence of BV was found among the Japanese (13.6%) and Thai women (15.9%). The microbial flora of women with BV were complex; the mean number of isolates recovered in the BV group was approximately 2 times more than that in a group of healthy women. Prevotella species, Porphyromonas species, Peptostreptococcus species, Mobiluncus species, Gardnerella vaginalis, and H2O2-nonproducing lactobacilli were significantly associated with BV. These organisms were less associated with H2O2-producing lactobacilli, which were predominant in women with normal flora, suggesting that H2O2-producing lactobacilli have antibacterial activity against BV-associated organisms. The vaginal sialidase assay by means of a filter-paper spot test was not proved to be a useful screening aid for diagnosis of BV because of the low sensitivity (69.4%) of this test.