For bacterial vaginosis, concurrent male partner treatment lowers recurrence rates
There were 2.6 fewer bacterial vaginosis recurrences per person-year among couples where both the male and female partner were treated compared with couples where only the female received treatment, a randomized trial in Australia found.
Having male partners take combined oral and topical antimicrobial therapy for bacterial vaginosis in addition to treating women resulted in a lower rate of recurrence within 12 weeks compared with standard care, according to a randomized controlled trial in Australia.
Researchers randomized 164 couples in which a woman had bacterial vaginosis and was in a monogamous relationship with a male partner between April 2019 and November 2023. In the intervention group (81 couples), the woman received first-line recommended antimicrobial agents for bacterial vaginosis and the male partner received oral and topical antimicrobial treatment (metronidazole, 400 mg, and 2% clindamycin cream applied to penile skin, both twice daily for seven days). In the standard care group (83 couples), the woman received first-line treatment and the male partner received no treatment.
Recurrence of bacterial vaginosis within 12 weeks, the primary outcome, was defined by both the presence of at least three Amsel criteria and a Nugent score of 4 to 10. After 150 couples had completed the 12-week follow-up period, the trial was stopped by the data and safety monitoring board because of the inferiority of standard care. Findings were published by the New England Journal of Medicine on March 6.
The modified intention-to-treat population consisted of 69 couples in the partner-treatment group and 68 couples in the control group. Twenty-four of 69 women (35%) in the partner-treatment group had a recurrence (recurrence rate, 1.6 per person-year; 95% CI, 1.1 to 2.4) compared to 43 of 68 women (63%) in the control group (recurrence rate, 4.2 per person-year; 95% CI, 3.2 to 5.7), corresponding to an absolute risk difference of −2.6 recurrences per person-year (95% CI, −4.0 to −1.2; P<0.001) and a hazard ratio of 0.37 (95% CI, 0.22 to 0.61) with partner treatment.
The average time until recurrence was 73.9 days in the intervention group and 54.5 days in the control group (difference in restricted mean survival time, 19.3 days [95% CI, 11.5 to 27.1]; P<0.001). Adverse events among treated men included nausea, headache, and metallic taste. Results were consistent across sensitivity and secondary analyses, with no differences seen based on use of intrauterine devices (IUDs) and circumcision status.
The researchers highlighted the high burden of risk for recurrence among the trial population, with 87% of women having a history of bacterial vaginosis, 80% having an uncircumcised male partner, and nearly one-third using an IUD. Limitations to the study include its early end at the interim analysis and the fact that most participants were of Western Pacific and European ethnic background.
“Our trial showed that treating male partners with a week of oral metronidazole and topical clindamycin, together with treatment of women, resulted in a lower rate of recurrence of bacterial vaginosis within 12 weeks than treatment of the woman alone,” the authors concluded.
An accompanying editorial said the results constitute a major paradigm shift, noting “they provide substantial evidence supporting the role of sexual transmission of bacterial vaginosis-associated bacteria, particularly within regular sexual partnerships.”
The study underscores the need to update the treatment approach to bacterial vaginosis in women, specifically regarding how they should be counseled on the origin of their infection, and the need to engage male partners in sharing responsibility for transmission and treatment, the editorialists noted. “This trial provides data critical to educating clinicians and patients about the role of sexual transmission of bacterial vaginosis-associated bacteria and the benefit of male-partner treatment,” they wrote.