Male Partner Treatment for Bacterial Vaginosis
Direct Recommendation
For recurrent bacterial vaginosis, treat the male partner with oral metronidazole 400 mg twice daily for 7 days PLUS 2% clindamycin cream applied to penile skin (including under the foreskin if uncircumcised) twice daily for 7 days, based on landmark 2025 trial evidence showing a 28% absolute reduction in recurrence rates. 1
For first-episode BV, male partner treatment is not routinely recommended, as traditional guidelines state it does not prevent recurrence. 2, 3
Evidence-Based Treatment Algorithm
When to Treat Male Partners
Treat male partners in these scenarios:
- Recurrent BV (defined as ≥2 episodes within 6-12 months): The 2025 StepUp trial demonstrated that concurrent partner treatment reduced recurrence from 63% to 35% at 12 weeks (absolute risk reduction of 28%), which was so significant the trial was stopped early for efficacy. 1
- Women in monogamous heterosexual relationships with regular male partners 1
Do NOT routinely treat male partners for:
- First episode of BV, as older evidence (six randomized trials) showed no benefit 4
- Women without regular male partners 2
The Evolving Evidence Landscape
This represents a major shift in clinical practice. The CDC historically stated that treating male partners does not prevent BV recurrence based on six older trials. 2, 4 However, the 2025 New England Journal of Medicine trial used a novel combination approach (oral PLUS topical antibiotics) that previous studies did not employ, which may explain the dramatic difference in outcomes. 1
The American College of Obstetricians and Gynecologists now acknowledges this newer evidence and may recommend partner treatment for recurrent cases. 4
Specific Treatment Protocol for Male Partners
Prescribe both medications simultaneously:
- Oral metronidazole 400 mg twice daily for 7 days 4, 1
- 2% clindamycin cream applied to glans penis and upper shaft (under foreskin if uncircumcised) twice daily for 7 days 4, 1
Critical patient counseling points:
- Abstain from ALL alcohol during treatment and for 24 hours after completion to prevent disulfiram-like reactions 4, 5
- Refrain from unprotected intercourse for at least 14 days to allow treatment to take effect 4
- Adherence is crucial: women whose partners adhered to medication had significantly better outcomes 6
Common Adverse Effects in Treated Men
Men may experience nausea, headache, and metallic taste, but the treatment is generally well-tolerated. 1 A 2021 pilot study of 34 couples showed high acceptability and tolerability of the combination therapy. 7
Follow-Up Strategy
For women:
- No routine follow-up needed if asymptomatic 4, 5
- Return if symptoms persist after treatment completion or recur 4, 5
- Pregnant women require follow-up evaluation one month after treatment 4
For male partners:
- No routine follow-up needed for asymptomatic men 4
Important Clinical Caveats
Why the combination approach matters: The 2025 trial used BOTH oral and topical antibiotics for men, targeting both urethral and penile skin colonization with BV-associated bacteria. 1 Previous trials using oral metronidazole alone showed no benefit. 6 Microbiological studies demonstrate that BV-associated bacteria colonize both the male urethra and penile skin, and the combination therapy significantly reduces bacterial load at both sites. 7
Recurrence remains common: Even with partner treatment, 35% of women still experienced recurrence within 12 weeks, though this is substantially better than the 63% recurrence with standard care. 1 This may be due to biofilm formation, incomplete eradication, or other factors beyond sexual transmission. 5
Sexual transmission evidence: Women who have never been sexually active rarely develop BV, and BV is associated with multiple partners and frequency of intercourse, supporting a sexual component to transmission. 2, 4 However, BV is not classified as a classic sexually transmitted infection. 4