References UK clinical guidance from the NHS, the British HIV Association (BHIVA), and the British Association for Sexual Health and HIV (BASHH). Last updated: April 2026.
Bacterial vaginosis (BV) is a common vaginal condition caused by an imbalance in the natural bacteria. It’s more common in women living with HIV, and research suggests BV may increase the risk of both acquiring and transmitting HIV. Understanding the link helps you manage both conditions effectively.
Here’s what to know about BV and HIV.
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What Is Bacterial Vaginosis?
BV occurs when the normal lactobacilli bacteria in the vagina are replaced by an overgrowth of other bacteria, particularly Gardnerella vaginalis. It’s not an STI, but it’s associated with sexual activity and is common in women who have sex with women.
Symptoms
- Thin, greyish-white vaginal discharge
- A fishy smell, often stronger after sex
- Mild irritation or itching (less common)
- Many women have no symptoms at all
The BV-HIV Link
| Direction | What the Evidence Shows |
|---|---|
| BV increases HIV acquisition risk | BV disrupts the vaginal barrier and increases inflammation, making it easier for HIV to enter |
| BV increases HIV transmission risk | BV raises vaginal HIV viral load, increasing the risk of passing HIV to sexual partners |
| HIV increases BV risk | Immune changes in HIV may alter vaginal flora, making BV more common and harder to treat |
Treatment
BV is treated with antibiotics:
- Metronidazole — oral tablets or vaginal gel (most common)
- Clindamycin — vaginal cream (alternative)
Neither interferes with HIV medication. Recurrence is common — up to half of women experience BV again within 12 months.
Reducing Recurrence
- Avoid douching or vaginal washing products
- Use water only or a gentle unperfumed wash externally
- Avoid perfumed soaps, bubble bath and vaginal deodorants
- Some evidence supports vaginal probiotics, though more research is needed
- Treat sexual partners if BV keeps recurring (especially female partners)
Why It Matters for Women with HIV
Treating BV promptly reduces vaginal inflammation and may lower the risk of passing HIV to partners. If you are on ART with an undetectable viral load (U=U), sexual transmission of HIV is not possible regardless of BV status. But treating BV is still worthwhile for comfort and general vaginal health.
Read more: What is HIV? | Cervical screening and HIV | Female-to-female transmission
Frequently Asked Questions
Is BV an STI?
BV is not classified as an STI, but it’s associated with sexual activity and is more common in women with new or multiple partners.
Can BV affect my HIV treatment?
BV does not interfere with ART. Metronidazole and clindamycin are safe with HIV medication.
Should my partner be treated for BV?
Current UK guidelines don’t routinely recommend treating male partners. For female partners, treating both women may help reduce recurrence.
Related reading
- Can You Test for STIs While on Your Period?
- Does a Vaginal Yeast Infection Smell?
- How Different STIs Affect Vaginal Discharge
- Lab-Based Vaginitis Test
- What Is a Female (Internal) Condom?
Sources
- NHS — Sexual health conditions
- BASHH — UK clinical guidelines for STI management
- British HIV Association (BHIVA) — HIV treatment guidelines
- Terrence Higgins Trust — sexual health information
- UK Health Security Agency — STI surveillance data
Steve Page is a recognised expert on Sexually Transmitted Diseases (STDs) and STD treatments, having published numerous articles in peer-reviewed journals and presented his research at conferences around the world. He has an in-depth understanding of the latest medical research on STDs, and is an advocate for the development of new treatments and protocols to improve the health of those affected. In addition to his research, he has dedicated his career to understanding the causes and symptoms of STDs, as well as how to best treat those impacted.
