Prevalence of bacterial vaginosis and vaginal flora changes in peri- and postmenopausal women

Abstract

Our aim was to evaluate the prevalence of bacterial vaginosis and decrease in lactobacillus colonization in women 40 years old or older in relation to menopausal status by evaluation of Gram-stained smears. A total of 1,486 smears from Italian Caucasian women aged 40 to 79 years were examined. Women were classified as follows: fertile (regular cycles) (n = 328), perimenopausal (irregular cycles) (n = 237), and postmenopausal (n = 921), including 331 women on estroprogestinic hormone replacement therapy (HRT). The prevalences of bacterial vaginosis (assessed as a Nugent score of >or=7) in fertile (9.8%) and perimenopausal (11.0%) women were not statistically different, whereas the prevalence was significantly lower overall in postmenopausal women (6.0%) (P = 0.02). Specifically, 6.3% of postmenopausal women without HRT and 5.4% of postmenopausal women with HRT were positive for bacterial vaginosis. The Nugent score system was not adequate for evaluating the normal and intermediate vaginal flora in women over the age of 40 years. High numbers of peri- and postmenopausal women had no lactobacilli and no bacterial-vaginosis-associated microorganisms. This nonpathological absence of lactobacilli in women with a Nugent score of 4 was scored as 4*, and this group was considered separately from the intermediate flora group. A score of 4* was obtained for 2.1% of fertile women, 11.4% of perimenopausal women, 44.1% of postmenopausal women without HRT, and 6.9% of postmenopausal women with HRT. The physiological reduction in lactobacillus colonization of the vagina in postmenopausal women does not cause an increase in bacterial-vaginosis prevalence. Reversion of lactobacillus flora to premenopausal levels due to HRT does not increase the prevalence of bacterial vaginosis in postmenopausal women.

FIG. 1.

Gram-stained vaginal smear from a postmenopausal woman with a score of 4∗ (magnification, ×400). Epithelial cells are visualized; bacteria are absent.

FIG. 2.

Profile of full lactobacillus colonization (stippled bars) and of score 4∗ (physiological absence of lactobacilli) (dark shaded bars) in subgroups of women over the age of 40 years.