Bacterial vaginosis (BV) discharge is typically thin, watery, and greyish-white. It coats the vaginal walls evenly and has a distinctive fishy smell, especially after sex. This looks and feels quite different from normal discharge, which tends to be clear or slightly white and varies in thickness throughout the menstrual cycle.
Color, Texture, and Smell
The hallmark of BV discharge is its thin, milklike consistency. Rather than being thick or clumpy, it’s smooth and watery, often described as homogeneous, meaning it looks uniform rather than having visible chunks or variation in texture. The color ranges from off-white to grey, sometimes with a slightly yellowish tint. You might notice it most on underwear or when wiping.
The smell is often what gets people’s attention first. BV produces volatile compounds called amines, which create a strong fishy odor. This odor becomes noticeably worse after sex because semen is alkaline, and that chemical interaction releases more of these compounds into the air. Some people describe the smell as mild, while others find it quite strong and persistent throughout the day.
How BV Discharge Differs From a Yeast Infection
This is one of the most common points of confusion. BV and yeast infections are different conditions with visually distinct discharge, and telling them apart can save you from using the wrong over-the-counter treatment.
- BV discharge: Thin, grey or white, watery, fishy-smelling. More noticeable after sex.
- Yeast infection discharge: Thick, white, with a cottage cheese-like consistency. Little to no odor, but significant itching and irritation.
If your discharge is thin and smells fishy, that pattern points toward BV. If it’s thick, lumpy, and your main complaint is intense itching rather than odor, a yeast infection is more likely. Both can cause some burning during urination, so that symptom alone won’t help distinguish between them.
Other Symptoms Beyond Discharge
Discharge and odor are the primary signs of BV, but some people also experience vaginal itching, a burning sensation when urinating, or general discomfort. These symptoms tend to be milder than what you’d feel with a yeast infection, where irritation and swelling are usually front and center.
Here’s the surprising part: roughly half of all people with BV have no noticeable symptoms at all. The bacterial imbalance is present, but the discharge changes are too subtle to detect or the odor isn’t strong enough to register. This is why BV sometimes gets picked up incidentally during a routine exam rather than because something felt wrong.
What Causes the Discharge to Change
Normal vaginal discharge is maintained by a community of beneficial bacteria, primarily Lactobacillus species, which keep the environment slightly acidic. In BV, the population of these protective bacteria drops sharply and gets replaced by a surge of anaerobic bacteria. This shift raises the vaginal pH above 4.5 (normal is around 3.8 to 4.5) and changes the chemical composition of vaginal fluid, producing those fishy-smelling amines and altering the discharge’s color and consistency.
BV isn’t a sexually transmitted infection, though sexual activity can trigger the bacterial shift. Douching, new sexual partners, and anything that disrupts the vaginal microbiome can contribute. The discharge you see is essentially a visible sign that the bacterial balance has tipped in the wrong direction.
How BV Is Confirmed
If you’re unsure whether what you’re seeing is BV, a healthcare provider can test for it quickly. The standard approach checks for at least three of four signs: the characteristic thin, milklike discharge; a vaginal pH above 4.5; the fishy smell (sometimes tested by adding a solution to a sample); and the presence of “clue cells” under a microscope, which are vaginal cells visibly coated in bacteria. Most of these results come back during the same visit.
What to Expect During Treatment
BV is treated with a course of antibiotics, either taken orally or applied as a vaginal gel or cream. Most people notice the discharge and odor improving within a few days of starting treatment, though completing the full course is important even after symptoms clear.
One frustrating aspect of BV is its recurrence rate. Many people find that discharge and odor return within a few months of treatment. This doesn’t mean the antibiotics failed. It reflects how easily the vaginal microbiome can be disrupted again. If BV keeps coming back, longer or repeated treatment courses are sometimes used to help maintain the bacterial balance.