Bacterial vaginosis (BV) produces a thin, white or gray discharge with a milk-like consistency that coats the vaginal walls evenly. Unlike the chunky discharge of a yeast infection, BV discharge is smooth and watery, often with a noticeable fishy smell. That said, more than half of all women with BV have no visible symptoms at all, which makes it easy to miss.
What BV Discharge Looks Like
The hallmark of BV is a thin, homogeneous discharge that looks grayish-white. It has a smooth, almost milky texture and tends to coat the vaginal walls in an even layer rather than clumping or collecting in thick patches. The volume can be heavier than your normal discharge, which is often what prompts people to notice something is off.
Color ranges from off-white to gray. Some women describe it as looking slightly “dingy” compared to the clear or white discharge they’re used to. It won’t typically look yellow, green, or chunky. If you’re seeing those colors or textures, a different infection is more likely.
The Smell Is Often the Biggest Clue
BV is strongly associated with a fishy odor, and for many women this is more noticeable than the visual changes. The smell comes from specific compounds (putrescine, cadaverine, and tyramine) that bacteria produce in high concentrations when the vaginal balance shifts. These are the same chemicals responsible for the smell of decaying organic matter, which is why the odor is so distinctive.
The smell tends to be strongest after sex and after your period. Semen is alkaline, and that pH shift releases more of those odor-causing compounds. The same thing happens during menstruation, when blood temporarily raises vaginal pH.
What BV Doesn’t Look Like
BV does not typically cause visible redness, swelling, or inflammation of the vulva or labia. The CDC does not list these as BV symptoms. If you’re seeing redness and significant swelling alongside discharge, that pattern points more toward a yeast infection or another type of vaginitis.
This is one of the easiest ways to tell BV apart from a yeast infection at home:
- BV discharge: Thin, grayish-white, smooth, fishy-smelling. Irritation is mild if present at all.
- Yeast infection discharge: Thick, white, cottage cheese-like texture with little to no odor. Intense itching, burning, and sometimes visible redness or swelling of the vulva.
BV can cause some itching around the outside of the vagina and mild burning when you pee, but pain is not a typical feature. If you’re experiencing significant pain, especially during or after sex, that’s worth investigating as a separate issue.
Why You Might Not See Anything at All
More than half of women with BV are completely asymptomatic. They have the bacterial imbalance, but no unusual discharge, no odor, and no discomfort. This is why BV is sometimes caught incidentally during a routine exam rather than because of something you noticed yourself.
If you do have symptoms, they can range from barely noticeable to hard to ignore. Some women only pick up on a faint change in smell. Others deal with heavy, persistent discharge that soaks through underwear. The severity doesn’t necessarily reflect how “bad” the infection is. It has more to do with which bacteria have overgrown and how your body responds.
How BV Is Confirmed
Because BV discharge can look subtle or overlap with normal variation, visual inspection alone isn’t enough for a diagnosis. Clinicians use a set of criteria that go beyond appearance. A positive diagnosis generally requires at least three of the following: the characteristic thin, coating discharge; a vaginal pH above 4.5 (healthy vaginal pH sits below that); a fishy odor; and the presence of “clue cells” under a microscope.
Clue cells are vaginal skin cells that have become so covered in bacteria they look fuzzy or stippled under magnification. For the finding to count toward a BV diagnosis, more than 20% of the cells on the slide need to look this way. This is something only a lab or clinical exam can confirm, which is why at-home diagnosis based on discharge alone is unreliable.
What Changes Your Vaginal pH
A healthy vagina is acidic, with a pH below 4.5. That acidity keeps harmful bacteria in check. When pH rises above 4.5, the environment shifts in favor of the anaerobic bacteria responsible for BV. Several everyday things can push pH higher: unprotected sex (semen has a pH around 7 to 8), menstrual blood, douching, and certain soaps or washes used internally.
This is why BV often shows up after a new sexual partner, after a period, or after douching. The discharge and odor you notice are downstream effects of that pH shift and the bacterial overgrowth it allows. Restoring the acidic environment is the basic goal of treatment, which typically involves a course of antibiotics that target the overgrown anaerobic bacteria while leaving the protective bacteria intact.