What Is BV for Females? A Plain-Language Guide to Bacterial Vaginosis

Maybe you've noticed a thin, grayish discharge or a fishy odor and typed "what is bv for females" into a search bar at midnight. Bacterial vaginosis is a change in the vagina's usual bacterial balance, not a sign of poor hygiene. This guide covers what BV is, what tips that balance, and what the evidence shows.

TL;DR

What Is BV for Females, and What Does It Look Like?

Bacterial vaginosis is a change in the vagina's usual bacterial community. It can affect women at any adult age. Reviewers describe BV as a shift from Lactobacillus-dominated flora to a mix of anaerobes such as Gardnerella, Atopobium and Prevotella ¹¹. In a healthy state, about 70% of women ¹⁵ have flora led by L. crispatus, L. gasseri, L. jensenii or L. iners. A survey of 396 women described five vaginal community types, and four of them were dominated by a single Lactobacillus species ¹⁰. Those lactobacilli produce lactic acid at about 110 mM, which keeps vaginal pH near 3.5.

In BV, pH rises above 4.5 ¹². When lactobacilli dominate, measured pH averaged about 3.5 (range 2.8 to 4.2) in 56 healthy women ⁹. Deep sequencing in 220 women found that BV communities were diverse, with no single species shared by all of them ⁴. A 2016 expert review concluded that the exact cause of BV is still debated ⁵, so a clinician's test is the way to confirm it.

What Causes BV, and Can I Get BV From a Guy?

BV develops when protective lactobacilli lose ground to mixed anaerobic bacteria. Sex, the menstrual cycle and leftover biofilm can all shape that shift. Reviewers link BV recurrence to bacteria or biofilm that persist after antibiotics and to reinfection from sexual partners ⁶. When researchers tracked 32 women for 16 weeks, vaginal communities shifted quickly with the menstrual cycle and with sex, even in healthy women ¹⁷. BV is not classed as a sexually transmitted infection, but partners clearly matter. A 2025 NEJM trial found that also treating male partners cut 12-week BV recurrence from 63% to 35% ¹⁴.

That result supports the idea that a partner can reseed BV-type bacteria after treatment. It does not mean a partner is the only cause. Other infections can also be present alongside BV. In 290 lab swabs, STIs were more common in women with BV (28%) than in women without it (20.4%) ⁷. That is one more reason to get tested rather than guess. For help with a common mix-up, see our guide to BV vs yeast infections.

Why Do I Keep Getting BV? Understanding Recurrence

BV recurrence means symptoms and abnormal flora return after successful treatment. It is common, even when the antibiotic course was completed correctly. In one cohort, 58% of women ³ had BV again within 12 months of standard oral metronidazole. One leading explanation is a bacterial biofilm. In vaginal biopsies from 20 women with BV and 40 controls, Gardnerella vaginalis formed an adherent biofilm that was specific to BV ²⁴. A small 2008 follow-up study with no control group found that this biofilm returned on the vaginal wall after a week of oral metronidazole, even though the women had recovered clinically ²⁵.

Lab work points the same way. In a 2011 lab study, metronidazole left holes in lab-grown BV biofilms but did not clear the organisms ²⁶. A 2019 review found that treatments aimed at the biofilm itself have so far been tested mostly in lab studies ²⁷. If BV comes back, that does not mean you did anything wrong. Your flora may need ongoing attention, and a clinician can help you plan next steps.

How Is BV Diagnosed, and What About OTC BV Treatment?

A clinician diagnoses BV by checking vaginal pH and examining discharge under a microscope. Home strips cannot confirm BV, so this applies whenever symptoms appear. A pH above 4.5 is typical of BV ¹². Home pH strips can hint at a shift, but they cannot rule out an STI. Over-the-counter options are limited. Antibiotics remain the only FDA-approved BV treatments ⁸.

In a retrospective review of 58 women with recurrent BV, an antibiotic plus vaginal boric acid regimen had high early success, but half had failed by 36 weeks ¹⁶. That review had no control group. You can read more about that option in our overview of boric acid suppositories.

How Can You Support Your Body Naturally With BV?

Natural BV approaches are non-prescription steps such as probiotics and avoiding douching. They work as support, not as a replacement for diagnosis and antibiotics. A 2019 meta-analysis of 13 trials found that adding probiotics to antibiotics modestly raised the share of women cured (RR 1.28), while noting the evidence is not strong ¹³. A 2024 meta-analysis of 35 trials found that probiotics used alongside standard care were associated with better outcomes and fewer BV recurrences ¹⁹. A 2026 network meta-analysis found that oral probiotics after BV treatment reduced early recurrence (low-certainty evidence). In that analysis, only vaginal probiotics showed a significant long-term benefit overall ¹⁸.

To weigh the evidence in more depth, read our article on whether probiotics can cure BV.

Which Lactobacillus Strains Have Been Studied for BV?

Strain matters because results in this field differ from one trial to the next. Some oral strains have done well and others have not. In a 2006 trial of 125 women, oral L. rhamnosus GR-1 and L. reuteri RC-14 taken with metronidazole raised the 30-day share cured to 88%, compared with 40% on metronidazole alone ²⁰. In 64 healthy women, the same pair taken for 60 days shifted asymptomatic BV-type flora to normal in 37% of women, compared with 13% on placebo ¹. Other trials of those same strains found no benefit. In a 2021 trial of 126 women, adding them to metronidazole did not improve outcomes, and the strains were rarely detected in the vagina ²¹.

In a separate trial of 86 pregnant women, 12 weeks of these strains did not change vaginal flora more than placebo ²². Results also depend on which species a product contains. In a 2020 NEJM trial of 228 women, the vaginal L. crispatus product Lactin-V lowered 12-week recurrence to 30%, compared with 45% on placebo ². The species detected in healthy women vary as well. A 2012 study of 92 healthy women of reproductive age detected L. acidophilus in 39% of them, alongside more common species ²³. For more on how route affects results, see our guide to oral vs vaginal probiotics.

When Should You See a Clinician About BV?

Knowing what is bv for females is a useful start, but it cannot replace a proper diagnosis. Because antibiotics are the only FDA-approved option and BV often returns afterward ⁸, it is worth seeing a clinician whenever symptoms come back. Book an appointment if you notice a new grey or thin discharge, a fishy odor, itching or burning, especially if this is your first episode. If BV keeps returning, ask whether your partner should be treated too ¹⁴. Pregnancy changes the picture, so tell your clinician right away if you are expecting. Bring a list of your symptoms and any products you already use.

In summary, BV is a common shift in vaginal flora. It deserves testing and proper treatment, and a dietary supplement is never a substitute for that visit.

FAQ

Q: What is BV for females, and how do you get it?

A: Bacterial vaginosis is a common vaginal condition in which the usual bacterial balance shifts. Protective lactobacilli decline while other bacteria overgrow. It isn't classed as a sexually transmitted infection, but new or multiple partners, douching and smoking are linked to higher risk. It can also appear without any clear trigger.

Q: What does BV discharge look like?

A: BV discharge is typically thin and grayish-white, and it may coat the vaginal walls. Many people notice a fishy odor that is often stronger after sex or during a period. Itching or burning is less common than with yeast infections. Some people have no symptoms, so discharge alone can't confirm a diagnosis.

Q: Can I get BV from a guy?

A: BV isn't considered a classic STI, and men don't develop BV themselves. However, sexual activity can influence vaginal bacteria, and new partners are associated with BV. Treating male partners lowered recurrence in a recent trial. Using condoms may help some people. BV can also pass more directly between female partners.

Q: Why do I keep getting BV even after treatment?

A: BV often returns after antibiotics because treatment clears problem bacteria but doesn't always restore protective lactobacilli. Bacterial biofilms can survive therapy, and triggers like douching, scented products or an untreated partner may continue. If BV keeps recurring, ask a clinician about extended or suppressive treatment plans rather than simply repeating short courses.

Q: Is there an OTC option for BV?

A: In the US, the standard BV antibiotics, metronidazole and clindamycin, require a prescription. Over-the-counter options such as pH-balancing gels, boric acid suppositories and odor products may ease symptoms for some people, but they aren't proven fixes. Confirm the diagnosis first, because yeast infections and some STIs can look similar.

Q: Can probiotics help with BV?

A: Probiotics containing Lactobacillus strains are being explored as a way to support healthy vaginal flora. They are used alongside antibiotics rather than as a replacement. Evidence is still developing, and results vary by strain, dose and delivery route. Probiotics are generally considered low risk for healthy adults, but they shouldn't delay diagnosis.

Q: How do I support vaginal balance at home?

A: No home remedy is proven to clear active BV, but some habits support vaginal balance. Avoid douching and scented washes, wear breathable cotton underwear, use condoms and rinse the vulva with plain water. Putting garlic, tea tree oil or yogurt in the vagina may irritate tissue. If symptoms persist, prescription treatment is the reliable route.

Q: When should I see a doctor for BV?

A: See a clinician the first time you notice symptoms, if you're pregnant, or if BV keeps coming back. Seek prompt care for fever, pelvic pain, sores or unusual bleeding, because these may signal another infection. BV is linked to higher STI risk, so testing and proper treatment matter for your long-term health.