Highlights from this article 

  • Penile microbiomes are found on the skin and in the urethra of the penis. 
  • BV-associated bacteria can be found in the penile microbiome. Current research concludes that they are not directly harmful to people with penises.
  • Studies have found similarities between the penile microbiome and the vaginal microbiome of their partners. 
  • A new study from the CDC has concluded that BV can be sexually transmitted. Circumcised penises and using barrier methods such as condoms have been found to decrease the risk of transmitting BV-causing bacteria. 
  • There is currently no standard of care for partner treatment of BV. However, a small pilot study has seen promising success in both partners using oral and topical treatments simultaneously. 

BV (Bacterial vaginosis) is a condition caused by a disruptive bacterial community. People with vulvas may experience a fishy odor, discomfort, itchiness and grey, watery discharge.  

But what about people with penises? At Evvy, we are often asked by our community members whether or not partners can be treated for BV. As BV can cause so much discomfort for people with vaginas (if you know, you know), it’s often on us to start the conversation because we feel burdened with guilt for having an infection in the first place! It is never your (or your vagina’s) fault for having BV and by no means should you feel bad about it! So, we rounded up the most recent data and medical recommendations to make navigating it all a little easier. 

What is BV? 

First, a quick review of BV. (We have more in-depth information in this article, but here are a few helpful facts):  

  • BV is not caused by one specific type of bacteria. Rather, it refers to the condition of bacterial imbalance in the vaginal microbiome (in other words, there are more disruptive bacteria than protective bacteria, like lactobacilli). 
  • According to the CDC, symptoms may include a thin white or gray vaginal discharge; pain, itching, or burning in the vagina; a strong fish-like odor, especially after sex; burning when peeing; and itching around the outside of the vagina.

Wait, penises have a microbiome?

Yes, they do! There are two areas scientists look at when studying penile microbes: 

  1. The skin on the surface of the penis: A swab of the coronal sulcus (CS), the groove between the shaft and the head of the penis, can be used to assess the microbiome. This area harbors a stable bacterial community. For uncircumsized penises, the foreskin covers the CS. Circumcised and uncircumcised penises appear to have different CS microbiomes
  2. The urethral microbiome: This area can be assessed with a swab at the opening of the urethra (medically known as the urinary meatus), or by a urine sample

One study shows that the CS microbiome is more stable over time than the urethral microbiome. These two communities are also found to be distinct from one another. 

Can BV-associated bacteria be found in the penile microbiome?

Yes! Multiple studies have shown that BV-associated bacteria can be found in the CS (surface) penile microbiome and sometimes in the urethra. 

A 2015 study performed in Uganda established seven Community State Types (CSTs) for penile microbiomes, different from the five vaginal CSTs. 

Although each microbiome is unique, a CST describes the general categories of microbiomes, for example, what bacteria is dominant. The seven penile CSTs are different from the five vaginal CSTs

People with penile CSTs 4-7 had higher prevalence and abundance of BV-associated bacteria and were most likely to have a partner experiencing BV. 

Additionally, one study published in 2016 found that the composition of the penile skin microbiome is similar to their partner’s vaginal microbiome, and that the similarity becomes stronger when a partner is experiencing BV. Basically, if you and your partner have reached the “finish each other’s sentences” or have figured out how to finish with each other stage of your relationship (are these real things or only in our rom-com fantasies?), you might be sharing microorganisms. 

So, is BV sexually transmitted?

While the precise cause of BV remains unclear (frustrating we know, given how many people get BV every year), a new CDC report has finally recognized that BV can be sexually transmitted. Anecdotally, many members  of our TikTok community can attest to this! 

There is a significant amount of clinical data suggesting that BV-associated microbes can be shared between penile and vaginal microbiomes during sex. P.S. microbes can also be shared between vulvas during same-sex intercourse. 

This is one potential explanation for why it can be so hard to treat recurrent BV, as you and your partner(s) could be swapping the same microbes back and forth. 

Concurrency (having multiple sexual partners) was also found to be an increased risk factor for sexually transmitted BV. 

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How does one prevent transmitting BV-causing bacteria through sex?

Consistent condom use can lower the risk of BV by providing a barrier. Dental dams are another barrier method that can be used to protect your vulva from disruptive bacteria. While we know the ship has likely sailed, circumcision has also been found to decrease the risk of sexually transmitting BV-causing bacteria. 

However, it’s important to remember that a sexual partner’s microbiome is only one of multiple factors that can contribute to the state of your vaginal microbiome. There are other factors such as hormones, your period, and vaginal products that can increase your risk of BV. 

Should my partner seek treatment if I have BV?

As far as we know, BV-causing bacteria in the penile microbiome are not harmful to people with penises. (For the record, we have a feeling there would be more research on BV if they were.) The purpose of treating the penile microbiome is to decrease your risk of re-acquiring BV-associated microbes into your vaginal microbiome. 

Unfortunately, right now there is no standard, effective strategy that doctors can use for partner treatment. Multiple studies have tried different ways of giving a partner of someone with BV an oral antibiotic, and none of these studies indicated an effective benefit over a placebo. 

However, there is hope on the horizon. A recent pilot study was performed with 34 couples where partners were given both oral and topical antibiotic treatments. This study indicated that combination oral and topical partner treatment reduced BV-causing bacteria in both penile and vaginal microbiomes for 12 weeks. Because of the small nature of the study, the results will need to be tested further by increasing the number of participants to effectively assess symptoms and recurrence. The same research group has received approval for a larger study and appears to be actively enrolling patients through the Australian New Zealand Clinical Trials Registry. Fingers crossed! 

For now, if you are struggling with recurrent BV and are interested in partner treatment, both you and your partner should discuss the current evidence and options available with your physicians. Need tips on how to start that conversation? Evvy advisor and practicing OB-GYN Dr. Diana Currie has some great advice on our blog!

Help, I’m scared to talk to my partner about BV treatment! 

It can be nerve-wracking to talk about vaginal health with a partner, but we’re here to help! 

First, remember that vaginal infections are incredibly common. Cultural messages (and trolls on social media) tell us that talking about vaginas is dirty, but there is nothing to be ashamed of. It’s a good idea to avoid pointing fingers. Interestingly enough, a 2020 study of men’s perception of BV partner treatment found that men who had stigmatized views of STIs were less likely to jump to fears of infidelity with a BV diagnosis. In any case, vaginal infections are a part of being sexually active, especially if you’re prone to them. It doesn’t mean that either of you are to blame. 

Being direct and honest is the best approach. Remember that both partners are responsible for maintaining sexual health. In fact, the same 2020 study found that men saw accepting partner treatment as a demonstration of care and support for their partner. 

We hear from customers every day who feel guilty for having BV. Research shows that women commonly report feeling embarrassed, ashamed, or dirty about BV. But as the research on BV-causing bacteria shows, microbes do not always discriminate by gender or body parts. While it can feel wildly unfair that people with vulvas bear the brunt of the unpleasant symptoms, it doesn’t mean that we should have to hold onto shame, too.