Do vaginal infections stem from penile bacteria transmitted during sex? A new study out of the United States has examined this question.
Bacterial vaginosis is an infection which affects more than 20% of women worldwide. Caused by an imbalance in the normal vaginal microbiome, this infection can increase the risk of premature birth when it occurs during pregnancy.
Although previous studies have provided strong evidence that the genital bacteria of sex partners can be exchanged in the event of bacterial vaginosis, the question of whether bacteria present on the penis is a cause of this infection has not, until now, been examined in depth.
Scientists at the University of Illinois at Chicago compared the microbiota of 168 heterosexual couples in Kenya. At the beginning of the study, none of the participants had bacterial vaginosis, but a year later, more than 31% of the women had developed it.
Published in the journal Frontiers in Cellular and Infection Microbiology, the study's results suggest a link between the overall makeup of a man's microbiome and the appearance of bacterial vaginosis in his female partner in the following year.
For the authors of the study, there are two possible scenarios: either certain of the bacteria found in the microbiome of some men are transmitted to the vagina during intercourse, or the penile bacteria can contribute to a more general disruption in the natural balance of the vaginal microbiome and lead to bacterial vaginosis in the long term. They stated that further study is required to clarify this process.
"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. 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 BV," said Dr. Supriya D. Mehta, an epidemiologist at the University of Illinois at Chicago and first author of the study.