#Penis microbes may increase the risk of vaginal infections after sex

Women experiencing an awkward itch may have their male partners to blame.

Bacterial vaginosis, a highly common infection affecting nearly one in three (29%) women, can cause intense itching, abnormal discharge, burning urination and a foul smell.

Despite its prevalence, the source of the infection has remained a mystery — until a recent study released by epidemiologists at the University of Illinois at Chicago. They found that the microbiome of the penis may play a significant role since, like the gut, the male reproductive organ hosts a bacterial colony all its own.

The yearlong survey, published in Frontiers in Cellular and Infection Microbiology, looked at 168 heterosexual couples in Kenya. Initially, scientists tested each participant for their genital bacteria, while also confirming that the women involved did not already harbor an infection. Among the male group, researchers also noted that 56% of men had circumcised penises, a known factor in the makeup of the male member’s microbiota.

Test subjects were required to follow up at one, six and 12 months to monitor their bacterial activity over time. By the end of the study, 31% of the women overall had developed BV. The rate of infection was 37.3% if the man was uncircumcised versus 26.3% if the man was circumcised.

These findings suggest that the penis has a larger influence over the vagina’s health than previously thought. The scientists were able to identify 10 species of penile microflora that corresponded with cases of BV, such as Gardnerella and Sneathia sanguinegens, which have been implicated in prior studies on women with the vaginal infection.

However, they note that the correlation doesn’t exactly prove men or their hygienic habits are at fault. The authors pointed out that the study was not exactly conclusive, as only 46% of couples involved were counted at all four appointments during the 12-month trial. The fact the study group was among only heterosexual couples in Kenya also limits its scientific reach.

“I would like for clinicians, researchers and the public to be inclusive of male sex partners in their efforts to improve women’s reproductive health,” said the lead author of the study, Supriya D. Mehta, in a statement. “Not to place directionality or blame on one partner or another, but to increase the options and opportunity for improved reproductive health, and hopefully reduce stigma from bacterial vaginosis.”