Can Men Get Bacterial Vaginosis or Pass BV-Associated Bacteria?

Can Men Get Bacterial Vaginosis?

A person without a vagina cannot develop bacterial vaginosis (BV), because BV is a condition involving the bacterial balance inside the vagina. A man who retains a vagina can develop BV.

A partner with a penis may carry bacteria associated with BV without having BV themselves. These bacteria can be found on penile skin or in the urethra, and the person may have no symptoms. Carrying these bacteria does not mean that the penis or urethra has a diagnosed BV infection.

There is currently no routine clinical method for testing the penis for BV-associated bacteria. As a result, a partner with a penis generally cannot use a standard test to determine whether they are carrying these bacteria. Questions about partner treatment are therefore based on the affected partner's diagnosis, recurrence pattern, and the advice of a qualified clinician-not on a diagnosis of 'male BV.'

What BV Is and Who Can Develop It

Bacterial vaginosis is a vaginal dysbiosis, meaning that the usual balance of vaginal bacteria changes. Lactobacillus-dominant bacteria become less predominant, while other bacteria become more prominent. BV can cause vaginal discharge or odor, but many people have no symptoms.

Only someone with a vagina can develop BV. The condition is not a diagnosis that applies to the penis or to a person without a vagina. Genital symptoms in a person without a vagina therefore need a different evaluation rather than being labeled BV.

Symptoms that resemble BV are not specific to it. Vaginal discharge, odor, itching, or burning can occur with other vaginal infections or conditions, so symptoms alone cannot establish the diagnosis. A healthcare professional can assess the symptoms and determine whether BV or another cause is present.

The male-partner question is especially relevant when BV returns after treatment. Bacteria associated with BV may be exchanged between sexual partners, but that does not mean that every recurrence comes from a male partner or that either partner has done something wrong.

How Partners With a Penis May Affect BV

A partner with a penis may carry bacteria associated with BV on penile skin or in the urethra without experiencing symptoms. These bacteria may be exchanged during sexual activity. This provides one possible explanation for why sexual activity is associated with BV and why recurrence may sometimes follow treatment.

The exchange of bacteria does not mean that the partner with a penis has BV. BV remains a vaginal condition, and asymptomatic carriage is not the same as a diagnosed infection of the penis or urethra.

Testing also limits what can be determined in practice. There is no current clinical method routinely used to test penile skin or the urethra specifically for BV-associated bacteria. A partner therefore cannot reliably establish carriage through an ordinary BV test or use a test result to decide independently whether antibiotics are needed.

Research on partner treatment has focused particularly on recurrent BV. The findings suggest that, in some couples, treating both partners at the same time may reduce the chance that BV returns. They do not show that every recurrence is caused by a partner, nor that every partner with a penis should automatically receive treatment.

Is Bacterial Vaginosis an STI?

BV is associated with sexual activity, but it is not usually described as a conventional STI caused by one specific sexually transmitted pathogen. It is a change in the vaginal bacterial community rather than a single infection that can be traced to one organism and one transmission event.

Sexual activity can affect the bacterial environment of the vagina, and BV-associated bacteria may be exchanged between partners. New or ongoing sexual partnerships may therefore be relevant to BV risk or recurrence. BV can occur in people who have not recently had sex. A BV diagnosis does not prove that the condition was sexually transmitted.

It also does not establish infidelity, prove that a partner has an untreated STI, or identify one partner as the cause. The relationship between sex, bacterial exchange, and BV is more complex than a simple transmission model.

This distinction affects how partners approach recurrent BV. The issue is not necessarily that one person has a conventional infection that must be 'passed back' and forth. Rather, clinicians may consider whether concurrent treatment could reduce recurrence in particular couples, based on emerging evidence and local practice.

What the Partner-Treatment Trial Found

A 2025 open-label randomized trial studied 164 monogamous couples in which the woman had BV and had a male partner. The trial compared treatment of the woman alone with treatment of both partners. Among the 150 couples who completed the 12-week assessment, BV recurred in 35% of women when both partners were treated, compared with 63% when only the woman was treated. The study was stopped early after its prespecified efficacy threshold was met.

In the partner-treatment group, the male partners received oral metronidazole and clindamycin cream applied to penile skin for seven days, while the women received standard BV therapy. This was a studied prescription regimen, not a general instruction for people to obtain or use antibiotics without medical supervision.

The results apply to the population and circumstances examined: women with BV who had a regular male partner and were in a monogamous relationship. The trial assessed prevention of recurrence over 12 weeks. It did not show that a person without a vagina can develop BV, that symptomatic genital problems in men are BV, or that partner treatment is appropriate for every partnership or clinical situation.

The findings also should not automatically be extended to casual partnerships, same-gender partnerships, pregnancy, other populations, or jurisdictions with different medical guidance. Clinicians and health authorities may differ in how they apply this emerging evidence.

What Male Partners Should Do About Recurrent BV

When BV repeatedly returns, the affected partner can ask a qualified clinician whether concurrent treatment should be considered. The 2025 trial provides evidence for this approach in specific couples, but partner-treatment practices and access may vary by jurisdiction. It is not yet a universal instruction for every person with recurrent BV or every partner with a penis.

The regimen studied in the trial used prescription oral and topical antibiotics for the male partner at the same time as treatment for the partner with BV. That regimen should not be treated as self-care guidance. A clinician needs to decide whether partner treatment is suitable and prescribe medication appropriately. Leftover antibiotics should not be used.

There is no routine penile BV test that can identify which asymptomatic partners should independently obtain antibiotics. Treatment decisions therefore require clinical discussion rather than testing for 'male BV' or assuming that bacterial carriage is present.

A clinician can also consider the specific relationship, recurrence history, local guidance, and whether the symptoms attributed to BV have been accurately diagnosed. Medication suitability, including issues that could affect prescribing, should be assessed by the treating healthcare professional.

When Genital Symptoms Need Medical Evaluation

Penile discharge, burning, irritation, sores, or other genital symptoms should not be diagnosed as male BV. Because BV is a vaginal condition, these symptoms require assessment for other possible causes. Those causes may include sexually transmitted infections or noninfectious irritation, but symptoms alone cannot identify which explanation applies.

A person with genital symptoms should seek clinical evaluation rather than using antibiotics intended for a partner or assuming that treatment for recurrent BV will address the problem. Professional assessment can help determine whether testing or another form of care is needed.

The partner with a vagina should also seek an accurate diagnosis for discharge, odor, itching, burning, or recurrent symptoms. BV can be asymptomatic, and symptoms that resemble it can occur with other vaginal infections or conditions. Treating an assumed diagnosis without confirming the cause may miss a different problem.

The practical distinction is straightforward: a person without a vagina does not develop BV, but may carry or exchange BV-associated bacteria without symptoms. Recurrent BV should be discussed by both partners with a clinician, while genital symptoms in either partner should be evaluated according to the anatomy and possible causes involved.