Specific Bacteria May Reduce Infection Odds

OCTOBER 01, 2005

Lactobacilli bacteria in the rectum may lower the risk of vaginal infections, as reported by researchers in the Journal of Infectious Diseases (August 1, 2005). The results of the study are the "first to document that the lower gastrointestinal tract can also harbor lactobacilli, which are beneficial for vaginal health," said lead investigator Sharon L. Hillier, PhD.

For the study, 531 women had vaginal and rectal swabs taken. The researchers found lactobacilli in the vagina of 74% of the women and in the rectum of 51%. Overall, 80% of the participants had evidence of lactobacilli in the vagina or in the vagina and rectum. Amajority of the women (67%) had lactobacilli that produced hydrogen peroxide. The investigators explained that women missing hydrogen peroxide-producing lactobacilli in the vagina have greater risk of bacterial vaginosis.

The researchers hypothesized that rectal lactobacilli may help preserve the healthy balance of normal vaginal flora and that this, in turn, is linked with a lower rate of the adverse effects of bacterial vaginosis. Common forms of rectal hydrogen peroxide-producing lactobacilli found among the women were Lactobacillus crispatus (16%), L jensenii (10%), and L gasseri (10%). An analysis showed that only 13 (9%) of the 147 women with vaginal, or rectal and vaginal, L crispatus or L jensenii had bacterial vaginosis, compared with 12 (44%) of the participants with other hydrogen peroxide- producing lactobacilli.