The quickest way to tell a yeast infection from bacterial vaginosis (BV) is by the discharge and smell. A yeast infection produces thick, white, cottage cheese-like discharge with little to no odor, while BV causes thin, grayish-white discharge with a noticeable fishy smell. But the differences go deeper than that, and getting the distinction right matters because the two conditions require completely different treatments.
Discharge: The Most Reliable Clue
Discharge is the single most telling symptom you can evaluate on your own. With a yeast infection, the discharge is thick, white, and clumpy, often compared to cottage cheese. It tends to stick to the vaginal walls rather than flow freely. With BV, the discharge is thin, watery, and grayish-white. It coats the vaginal opening more evenly and may be more noticeable on underwear.
Neither type of discharge should contain blood. If you see blood outside your period, that points to something else entirely.
Smell Tells You a Lot
BV is strongly associated with a fishy vaginal odor that often becomes more intense after sex. This smell comes from chemicals released by the overgrown bacteria responsible for the infection. Most people with a yeast infection notice no unusual odor at all, or at most a mild, bread-like smell. If you’re noticing a strong, unpleasant odor, BV is the more likely culprit.
Itching, Burning, and Physical Discomfort
Yeast infections are the itchy ones. They typically cause noticeable itching and redness on both the vulva (the external skin) and inside the vagina. The irritation can range from mild to intense, and sex or urination may sting. Swelling of the vulva is common.
BV, by contrast, often causes little to no physical irritation. Many people with BV have no symptoms at all beyond the discharge and odor. Some experience mild burning during urination, but the intense external itching that defines a yeast infection is unusual with BV. If itching is your dominant symptom, a yeast infection is more likely. If odor is your dominant symptom, lean toward BV.
What’s Actually Happening Inside
Despite the similar location, these are fundamentally different types of infection. A yeast infection is caused by an overgrowth of fungus, most commonly Candida, that naturally lives in the vagina in small amounts. Something tips the balance (antibiotics, hormonal changes, a weakened immune system) and the fungus multiplies beyond what your body can keep in check.
BV is bacterial, not fungal. Your vagina normally maintains a population of “good” bacteria called lactobacilli that keep the environment slightly acidic. When those protective bacteria decline, other bacteria (called anaerobes) overgrow and take over. Douching is one of the most common triggers because it physically washes away the lactobacilli. Having a new sexual partner or multiple partners also increases the risk, though BV is not classified as a sexually transmitted infection.
What a Home pH Test Can and Can’t Do
You can buy vaginal pH test strips at most pharmacies. A healthy vagina typically has a pH between 3.8 and 4.5, which is moderately acidic. BV pushes that pH above 4.5 because the overgrown bacteria produce alkaline byproducts. Yeast infections, on the other hand, usually leave your vaginal pH in the normal range.
So if you test your pH and it’s elevated, that points toward BV (or another infection like trichomoniasis). If your pH is normal, a yeast infection is more consistent. The FDA notes that home pH tests show good agreement with a doctor’s assessment, but they come with real limitations: an elevated pH doesn’t confirm BV specifically, and a normal pH doesn’t rule out infection entirely. A pH test is a useful starting clue, not a diagnosis.
Why the Distinction Matters for Treatment
This is the most important reason to figure out which infection you’re dealing with: the treatments are not interchangeable. Using the wrong one won’t help, and it may give the actual infection more time to establish itself.
Yeast infections are treated with antifungal medications. Over-the-counter options like topical creams are widely available and typically clear an uncomplicated infection within two to three days of starting a three-day course. A single-dose oral antifungal is another common option, available by prescription. If you’ve had a yeast infection before and recognize the symptoms clearly, self-treating with an OTC antifungal is reasonable.
BV requires prescription antibiotics. There is no effective over-the-counter treatment for BV. If you suspect BV, you’ll need to see a healthcare provider to get the right medication. This is especially important during pregnancy: a meta-analysis of existing research found that BV roughly doubles the risk of preterm birth. Screening and treatment for BV is considered an important part of routine prenatal care.
When Both Keep Coming Back
Recurrence is frustratingly common with both conditions. Recurrent yeast infections are defined as three or more symptomatic episodes within a single year, with symptom-free gaps between them. About 5 to 8 percent of people with vaginas experience this pattern. Treatment for recurrent yeast infections involves a longer initial course followed by months of maintenance therapy to prevent flare-ups.
BV recurs even more frequently. Up to half of people treated for BV see it return within 12 months. The reason is that antibiotics kill off the overgrown bacteria but don’t necessarily restore the lactobacilli population, leaving the vagina vulnerable to another imbalance. If either condition keeps returning, that’s a clear sign to work with a provider on a longer-term management plan rather than repeating the same short-course treatment.
Quick Comparison at a Glance
- Discharge: Yeast infections produce thick, white, clumpy discharge. BV produces thin, grayish, watery discharge.
- Odor: Yeast infections have little to no smell. BV has a strong fishy odor, especially after sex.
- Itching: Yeast infections cause significant vulvar and vaginal itching. BV rarely causes itching.
- Vaginal pH: Normal with a yeast infection. Elevated (above 4.5) with BV.
- Treatment: Yeast infections respond to antifungals (available OTC). BV requires prescription antibiotics.
If your symptoms don’t fit neatly into one category, or if you’re experiencing symptoms for the first time and aren’t sure what you’re looking at, getting tested is the most reliable path. A provider can examine discharge under a microscope and check pH alongside other markers to give you a definitive answer in a single visit. Self-diagnosis is reasonable for a straightforward, recurring yeast infection you’ve seen before, but anything ambiguous benefits from professional confirmation.