Bacterial vaginosis (BV) produces a thin, grayish-white discharge that looks noticeably different from normal vaginal fluid. Unlike infections that cause dramatic redness or swelling, BV is mostly visible through changes in discharge alone, which is why many people search for what it actually looks like. Here’s what to watch for and how to tell it apart from other common infections.
What BV Discharge Looks Like
The hallmark of BV is a thin, watery discharge with a milk-like consistency. It tends to coat the vaginal walls smoothly and evenly rather than clumping or sticking in patches. The color ranges from off-white to gray, sometimes with a slightly yellowish tint. The volume is often heavier than what you’d normally expect.
Healthy vaginal discharge, by comparison, is clear or white and doesn’t have a strong smell. It can vary in thickness throughout your menstrual cycle, but it generally doesn’t have that uniform, thin, coating quality that BV discharge does. If your discharge has shifted from its usual appearance to something thinner, grayer, and more abundant, that visual change is one of the clearest signs of BV.
The Smell Is a Major Clue
BV is strongly associated with a fishy odor, and this is often what prompts people to look more closely at their discharge in the first place. The smell tends to be most noticeable after sex, because semen raises the vaginal pH and releases more of the odor-causing compounds produced by the overgrown bacteria. You might also notice it after your period for similar reasons. Not everyone with BV has a strong odor, but when present, it’s distinctive and hard to mistake for anything else.
What BV Doesn’t Look Like
One of the most useful things to know about BV is what it typically doesn’t cause. Redness, swelling, and itching of the vulva are not common with BV. The external skin usually looks normal. If you’re seeing significant redness, swelling, or a rash around the vulvar area, that points more toward a yeast infection, an allergic reaction, or another type of vaginitis rather than BV.
BV also doesn’t usually cause pain. Some people experience mild irritation, but sharp pain, burning during urination, or soreness during sex is more characteristic of other conditions.
BV vs. Yeast Infection: Visual Differences
These two get confused constantly because they’re both common and both involve abnormal discharge. But they look quite different once you know what to compare.
- BV discharge: Thin, grayish-white, watery, heavy in volume, with a fishy smell.
- Yeast infection discharge: Thick, white, clumpy, often described as looking like cottage cheese, with little to no odor.
The surrounding tissue tells a story too. BV rarely causes visible inflammation. Yeast infections frequently cause redness, swelling, and intense itching of the vulva. Yeast infections can also cause burning or pain, especially after intercourse, while BV generally does not. If you’re seeing thick, clumpy discharge with irritated, swollen skin, that’s more likely yeast. If you’re seeing thin, gray, fishy-smelling discharge with no external irritation, BV is the more likely culprit.
What Happens at a Diagnosis
A healthcare provider diagnoses BV by looking at a combination of signs rather than relying on appearance alone. The clinical standard requires at least three of these four findings: the characteristic thin, homogeneous discharge; a vaginal pH above 4.5 (a healthy vagina sits between 3.8 and 4.5); a fishy odor when the discharge is exposed to a chemical solution; and the presence of “clue cells” under a microscope. Clue cells are normal vaginal cells that have become so coated with bacteria that their edges look fuzzy or stippled, a visual confirmation that the bacterial balance has shifted.
You can’t see clue cells or measure pH at home, which is why the visual and smell characteristics matter so much for recognizing BV early. Home pH test strips are available and can tell you if your vaginal pH is elevated above 4.5, but a high pH alone doesn’t confirm BV since other infections can raise it too.
When BV Has No Visible Signs
About half of people with BV don’t have obvious symptoms. The bacterial imbalance is present, but the discharge changes may be subtle enough to miss, especially if you don’t have a strong baseline sense of what’s normal for you. In these cases, BV is often caught incidentally during a routine exam or screening. This is worth knowing because the absence of dramatic visual signs doesn’t rule BV out, particularly if you have a mild fishy odor or a slight change in discharge consistency that you’re not sure about.