Bacterial vaginosis (BV) is not a yeast infection. They are two distinct conditions with different causes, different symptoms, and different treatments. BV is caused by an overgrowth of bacteria in the vagina, while a yeast infection is caused by an overgrowth of fungus. The confusion is understandable because both involve vaginal discomfort and abnormal discharge, but telling them apart matters because treating one with the wrong medication won’t help.
What Causes Each Condition
A healthy vagina maintains a careful balance of microorganisms. When that balance tips in favor of certain bacteria, the result is BV. When it tips in favor of a type of fungus called Candida, the result is a yeast infection. The distinction is biological: bacteria versus fungus.
BV is the more common of the two and occurs most often in people who are sexually active, though it can develop without sexual contact. The CDC notes that researchers still don’t fully understand how sex contributes to BV, and treating a sexual partner doesn’t appear to prevent it. It is not classified as a sexually transmitted infection. Rather, it’s a microbiome imbalance where harmful bacteria outnumber the protective ones.
Yeast infections can be triggered by antibiotics (which kill off protective bacteria and let fungus flourish), hormonal shifts from pregnancy or birth control, and possibly diets high in sugar. Both conditions share some overlapping risk factors: douching, using scented soaps or tampons, smoking, and having multiple sexual partners can all disrupt the vaginal environment enough to set either one off.
How the Symptoms Differ
The fastest way to tell BV from a yeast infection at home is by the discharge.
- BV discharge is thin, grayish, sometimes foamy, and has a noticeable fishy smell. The odor often gets stronger after sex.
- Yeast infection discharge is thick, white, and clumpy, often compared to cottage cheese. It typically has no odor at all.
Yeast infections also tend to cause more external irritation: itching, burning, redness, and swelling around the vulva. BV, on the other hand, may cause little to no irritation and sometimes produces no obvious symptoms at all. Some people with BV only notice the smell.
Why a Correct Diagnosis Matters
Because the two conditions have different biological causes, they require completely different treatments. BV is treated with antibiotics, while yeast infections are treated with antifungal medications. Using an over-the-counter yeast cream when you actually have BV will not resolve the problem, and untreated BV carries real health risks.
One way healthcare providers distinguish between them is vaginal pH. A healthy vagina of reproductive age has a pH between 4.0 and 4.5, which is moderately acidic. BV pushes that pH above 4.5, making the environment less acidic. Yeast infections, interestingly, often leave the pH completely normal. This is one reason at-home pH test strips can offer a clue, though they can’t give a definitive diagnosis on their own.
In a clinical setting, providers look for a combination of signs: the type and consistency of discharge, elevated pH, a fishy odor when a chemical solution is applied, and the presence of specific cells under a microscope. Meeting three of these four criteria confirms BV.
Treatment for BV
BV requires a prescription antibiotic, either taken orally or applied as a vaginal cream or gel. You cannot treat it with over-the-counter products. The frustrating reality of BV is its high recurrence rate: somewhere between 50% and 80% of women experience it again within 6 to 12 months of finishing antibiotics. This is partly because antibiotics clear the harmful bacteria but don’t always fully restore the protective ones.
If BV keeps coming back, your provider may recommend a longer or repeated course of treatment. Reducing known triggers, like douching and scented products, can help lower the odds of recurrence, though it’s no guarantee.
Treatment for Yeast Infections
Yeast infections are more straightforward to treat. Over-the-counter antifungal creams and vaginal suppositories are widely available in 1-day, 3-day, and 7-day formulations. A single-dose prescription oral antifungal is another common option. Most uncomplicated yeast infections clear within a few days of starting treatment.
For recurrent yeast infections (generally defined as four or more episodes in a year), providers may prescribe a longer initial course followed by weekly oral antifungal doses for up to six months. Severe cases, where symptoms include extensive redness, swelling, or cracking of the skin, sometimes need a second oral dose a few days after the first.
When BV Goes Untreated
Yeast infections are uncomfortable but rarely dangerous. BV, however, can lead to more serious complications if left untreated. A meta-analysis of existing research found that BV roughly doubles the risk of preterm birth in pregnant women. It also increases susceptibility to sexually transmitted infections by disrupting the vagina’s natural defenses.
Because BV symptoms can be mild or easy to dismiss, many people don’t seek treatment. If you notice a persistent fishy odor or a change in discharge that doesn’t match the typical signs of a yeast infection, getting tested is worth the effort. The conditions look similar enough to cause confusion, but they’re different enough that the right diagnosis changes everything about how you treat them.