A landmark study has revealed that bacterial vaginosis (BV)—a condition affecting nearly one-third of women worldwide and linked to infertility, premature births, and newborn deaths—is actually a sexually transmitted infection (STI). This discovery could revolutionize BV treatment and prevention strategies.
Researchers from Monash University and Alfred Health at the Melbourne Sexual Health Centre published their findings today in the New England Journal of Medicine, offering new hope for reducing BV’s stubbornly high recurrence rates.
Study authors Professor Catriona Bradshaw and Dr. Lenka Vodstrcil highlight that the conventional approach of treating BV as a vaginal microbiome imbalance is ineffective for long-term management. Over 50% of women experience a recurrence within three months after completing the standard week-long antibiotic treatment.
With BV now classified as an STI, this research paves the way for new treatment strategies focused on targeting transmission and improving cure rates. The findings are expected to drive major changes in women’s health and STI management worldwide.
In their trial of 164 couples with BV in monogamous relationships, they found that treating BV as an STI, with both sexual partners treated simultaneously, achieves significantly higher cure rates than the current practice of only treating women.
In fact, they stopped the trial early when it became clear that BV recurrence was halved in the partner treatment group compared to treating women alone.
“This successful intervention is relatively cheap and short and has the potential for the first time to not only improve BV cure for women, but opens up exciting new opportunities for BV prevention, and prevention of the serious complications associated with BV,” Professor Bradshaw said.
Dr Vodstrcil said having BV was already known to increase the risk of contracting other STIs. “We’ve suspected for a long time that it’s a sexually transmitted infection (STI), because it has a similar incubation period (after sex) to most STIs and is associated with the same risk factors as STIs like chlamydia, such as change in sexual partner and not using condoms.”
Professor Bradshaw said while studies have shown that men may harbor bacterial species associated with bacterial vaginosis on the penile skin and inside the penis, previous trials that included male partners did not show improved cure rates in their female partners.
“This was interpreted as evidence against sexual transmission,” Professor Bradshaw said. “However, these studies had design limitations, and none used a combination of oral and topical antibiotics to adequately clear BV bacteria in men, especially from the penile-skin site.
“Our trial has shown that reinfection from partners is causing a lot of the BV recurrence women experience, and provides evidence that BV is in fact an STI.”
