Vaginal infections each have a distinct visual signature, and the appearance of your discharge is often the fastest clue to what’s going on. The three most common types, yeast infections, bacterial vaginosis, and trichomoniasis, produce noticeably different discharge in color, texture, and smell. Some infections also cause visible changes to the skin of the vulva or vaginal opening. Here’s what to look for and how to tell them apart.
What Normal Discharge Looks Like
Before identifying what’s abnormal, it helps to know the baseline. Healthy vaginal discharge is clear, milky white, or off-white. Its texture changes throughout your menstrual cycle: it can be watery, sticky, or stretchy depending on where you are in your cycle. Around ovulation, discharge often becomes extra slippery and wet. Normal discharge has little to no odor and doesn’t cause itching or irritation.
Volume varies from person to person, and some days you’ll notice more than others. That’s all within the range of normal. What signals an infection is a change in color, consistency, smell, or the appearance of symptoms like redness, swelling, or soreness that weren’t there before.
Yeast Infection
A yeast infection produces thick, white discharge that’s often described as looking like cottage cheese. It’s clumpy, sticks to the vaginal walls, and typically has little or no odor. The surrounding vulvar skin turns red and swollen, and the dominant symptom is intense itching.
In more severe cases, the irritation can progress to the point where the skin around the vaginal opening develops small tears, cracks, or sores from scratching and swelling. You might also notice soreness during urination or sex. One distinguishing feature of yeast infections is that they don’t usually shift the vagina’s natural acidity level. The pH stays around 4.0 to 4.5, which is why discharge from a yeast infection doesn’t develop a foul smell the way bacterial infections do.
If you look at the skin of the outer vulva, you may see what’s sometimes called “satellite” spots: small raised bumps or tiny pustules around the edges of the main area of redness. This pattern, a shiny red patch with smaller spots scattered at its borders, is a hallmark of a yeast (Candida) overgrowth on skin.
Bacterial Vaginosis
Bacterial vaginosis, or BV, looks quite different from a yeast infection. The discharge is thin, watery, and either white or gray. It coats evenly rather than clumping. The standout feature is a strong fishy odor, which often becomes more noticeable after sex.
BV doesn’t typically cause the redness, swelling, or itching that yeast infections do, which is why many people with BV notice the smell before they notice any visual change. In fact, some people with BV have no symptoms at all. The infection happens when the normal balance of bacteria in the vagina shifts: protective acid-producing bacteria decline, and other bacteria overgrow. This raises vaginal pH above 4.5, which is what produces that characteristic odor.
Trichomoniasis
Trichomoniasis, a sexually transmitted infection caused by a parasite, produces discharge that looks distinctly different from either yeast or BV. The discharge is yellow or green, thin, and frothy, sometimes with visible small bubbles. It carries a foul odor that’s more pungent than the fishy smell of BV.
The vulva and vaginal opening often appear red, swollen, and irritated. Itching can be significant. About 40% of people with trichomoniasis develop what’s called a “strawberry cervix,” where the cervix becomes dotted with tiny red spots from inflammation. This isn’t something you’d see yourself, but it’s something a healthcare provider would notice during an exam. Trichomoniasis also shifts vaginal pH significantly, often pushing it above 5.4 and sometimes as high as 6.5.
Infections That Cause Sores or Blisters
Not all vaginal infections show up as discharge. Some produce visible sores, blisters, or ulcers on the vulva, vaginal opening, or surrounding skin.
Genital herpes typically appears as a cluster of small blisters on a red base. These blisters break open into shallow, painful sores that eventually crust over and heal. They tend to appear in groups rather than as a single isolated spot. Outbreaks can also cause an unusual vaginal discharge alongside the sores.
Syphilis, in its first stage, produces a single firm, round, painless sore called a chancre. It can appear inside the vaginal opening, on the vulva, or on surrounding skin. Because it’s painless and may be inside the vagina where you can’t easily see it, syphilis sores frequently go unnoticed. In its second stage, syphilis can cause a rash that appears on the palms of the hands and soles of the feet, which is an unusual location that helps distinguish it from other conditions.
Chlamydia and Gonorrhea
These two sexually transmitted infections can cause changes in discharge, but the visual signs are often subtle or absent entirely, which is part of what makes them tricky. When symptoms do appear, gonorrhea tends to produce thick, cloudy, or sometimes bloody vaginal discharge. Chlamydia may cause an increase in discharge without a dramatic color change. Both can cause bleeding between periods or unusually heavy menstrual bleeding, which can be a warning sign even when discharge looks relatively normal.
Both infections can inflame the cervix, a condition called cervicitis. This may produce a yellowish discharge from the cervical opening and cause spotting after sex. Because these infections so often produce mild or no visible symptoms, they’re a common reason healthcare providers recommend routine STI screening rather than relying on visual signs alone.
Skin Irritation That Mimics Infection
Sometimes what looks like a vaginal infection is actually a skin reaction on the vulva. Allergic contact dermatitis from soaps, laundry detergent, wipes, or other products can cause redness, swelling, and itching that closely resembles a yeast infection. The key visual difference is that allergic reactions tend to produce well-defined, symmetrical red patches with dry or scaly skin, rather than the moist, clumpy discharge of a yeast infection. The irritation also tracks closely with where the product made contact.
If you’re seeing redness and irritation but your discharge still looks clear and normal, a skin reaction is worth considering before assuming you have an infection.
Quick Comparison by Discharge Type
- Thick, white, clumpy, no odor: likely a yeast infection
- Thin, gray or white, fishy smell: likely bacterial vaginosis
- Yellow or green, frothy, foul odor: likely trichomoniasis
- Thick, cloudy, or bloody: possibly gonorrhea
- Increased but not dramatically different: possibly chlamydia
- Blisters in clusters on red skin: possibly genital herpes
- Single painless firm sore: possibly syphilis
Many of these infections overlap in symptoms, and some produce very mild or no visible signs at all. Color and texture of discharge can point you in the right direction, but a healthcare visit with testing is the only way to confirm which infection you’re dealing with, especially since having more than one at the same time is common.