Should same-sex female partners both complete bacterial vaginosis (BV) treatment before engaging in sexual activity if one partner is confirmed positive with symptoms?

Treatment of Same-Sex Female Partners for Bacterial Vaginosis

Yes, both female partners should complete bacterial vaginosis treatment before resuming sexual activity when one partner has a confirmed positive BV diagnosis with symptoms. This recommendation is based on the most recent evidence showing that treating both partners significantly reduces BV recurrence rates.

Understanding BV in Same-Sex Female Partners

Bacterial vaginosis (BV) is a clinical syndrome resulting from replacement of normal vaginal Lactobacillus species with high concentrations of anaerobic bacteria. While BV is not traditionally classified as an exclusively sexually transmitted disease, it is strongly associated with sexual activity 1.

Key facts about BV transmission in female same-sex couples:

• Women who have never been sexually active rarely develop BV 1
• BV acquisition is associated with having multiple sex partners 1
• Sexual exchange of BV-associated organisms between partners can occur 2

Evidence for Partner Treatment

The most recent high-quality evidence from a 2025 randomized controlled trial demonstrates that treating both partners significantly reduces BV recurrence rates 2. While this study focused on male-female couples, the biological mechanism of bacterial transfer between partners applies to female same-sex couples as well.

The study found:

• Recurrence rate of 35% when both partners were treated vs. 63% when only one partner was treated
• This represents an absolute risk difference of -2.6 recurrences per person-year (95% CI, -4.0 to -1.2; P<0.001)

Treatment Recommendations

For the symptomatic partner with confirmed BV:

• First-line treatment: Metronidazole 500 mg orally twice daily for 7 days 1

Alternative regimens:

• Metronidazole 2g orally in a single dose
• Clindamycin cream 2%, one full applicator (5g) intravaginally at bedtime for 7 days
• Metronidazole gel 0.75%, one full applicator (5g) intravaginally twice daily for 5 days
• Clindamycin 300 mg orally twice daily for 7 days 1

For the asymptomatic partner:

The same treatment regimen should be used for the asymptomatic partner to prevent reinfection.

Important Precautions

1. Alcohol avoidance: Both partners should avoid alcohol during metronidazole treatment and for 24-48 hours afterward to prevent nausea, vomiting, and other adverse reactions 3

2. Sexual abstinence: Partners should avoid sexual contact until both have completed treatment and symptoms have resolved 2

3. Condom use: Consider using barriers for digital-vaginal and toy-sharing activities even after treatment completion

4. Monitor for candidiasis: BV treatment may result in vulvovaginal candidiasis that requires antifungal treatment 3

Managing Recurrent BV

If BV recurs despite treating both partners, consider:

• Extended course of metronidazole (500 mg twice daily for 10-14 days)
• Maintenance therapy with metronidazole vaginal gel 0.75% twice weekly for 3-6 months 4
• Evaluation for biofilm formation, which may protect BV-causing bacteria from antimicrobial therapy 4

Common Pitfalls to Avoid

1. Treating only the symptomatic partner: This approach leads to significantly higher recurrence rates 2

2. Inadequate treatment duration: Ensure full completion of the prescribed regimen

3. Resuming sexual activity too soon: Wait until both partners have completed treatment and symptoms have resolved

4. Not addressing potential biofilms: Persistent or recurrent BV may be due to biofilm formation that protects bacteria from antibiotics 4

By treating both partners and following these recommendations, you can significantly reduce the risk of BV recurrence and improve long-term outcomes for both individuals.