Vaginal discharge has a natural scent, and some degree of smell is completely normal. The vagina maintains its own ecosystem of beneficial bacteria that produce lactic acid, keeping the environment slightly acidic. This process creates a mild, musky, or slightly tangy odor that shifts throughout your menstrual cycle. A new or stronger smell usually traces back to a handful of common causes, most of them easy to address.
What Normal Discharge Smells Like
Healthy discharge typically has a faint, slightly sour or musky scent. You’ll notice it most at midcycle, around ovulation, when discharge volume increases. During your period, discharge may smell slightly metallic, like copper pennies, because menstrual blood contains iron. After your period ends, the metallic note fades.
The smell can also shift during pregnancy. Increased blood flow to the vagina and rising levels of estrogen and progesterone alter your vaginal pH, which can introduce scents you haven’t noticed before. None of these changes on their own signal a problem. The key distinction is between a mild, familiar odor and one that is strong, persistent, or accompanied by other symptoms like itching or unusual color.
Bacterial Vaginosis: The “Fishy” Smell
A strong, fishy odor is the hallmark of bacterial vaginosis (BV), the most common vaginal infection in women of reproductive age. BV happens when the balance of bacteria in the vagina tips away from the protective, acid-producing species and toward other types that thrive in a more alkaline environment. Those bacteria produce compounds called amines, which give off that distinctive fishy smell, often most noticeable after sex or during your period.
BV discharge is usually thin, grayish-white, and more watery than normal. It doesn’t always cause itching or irritation, so the smell may be the only thing that feels off. BV is treated with a short course of antibiotics, and it resolves quickly once the bacterial balance is restored. Left untreated, it can increase susceptibility to sexually transmitted infections and, during pregnancy, raise the risk of preterm delivery.
Trichomoniasis and Other Infections
Trichomoniasis is a sexually transmitted infection caused by a parasite. It produces a foul-smelling discharge that can be clear, white, yellow, or green, and often looks thin or frothy. The odor tends to be stronger and more unpleasant than the fishy scent of BV, and it’s frequently accompanied by itching, burning during urination, and irritation around the vulva.
Yeast infections, by contrast, don’t usually produce a strong odor. Discharge from a yeast infection is typically thick, white, and clumpy, sometimes described as resembling cottage cheese. If there’s any scent at all, it’s mild and slightly bread-like. So if smell is your primary concern, a yeast infection is less likely to be the cause than BV or trichomoniasis.
Forgotten Tampons and Foreign Objects
A sudden, intensely foul odor, sometimes described as rotting, can signal a retained tampon or other object in the vaginal canal. It’s more common than you might think, especially when a tampon is inserted near the end of a period and forgotten. The longer it stays in place, the more bacteria break down the material and surrounding fluids, producing a smell that’s hard to ignore.
If you suspect a forgotten tampon, you can often reach it yourself with clean hands. If you can’t, a healthcare provider can remove it quickly. Beyond the odor, leaving a tampon in longer than eight hours raises the risk of toxic shock syndrome (TSS), a rare but serious condition caused by toxin-producing bacteria. TSS affects roughly 1 to 3 out of every 100,000 women and primarily occurs in people ages 15 to 25 who use tampons. Symptoms include sudden high fever, a rash, dizziness, and muscle aches, and it requires emergency medical care.
Sweat and Skin Bacteria
Sometimes the smell you’re noticing isn’t coming from discharge at all. The groin is packed with apocrine sweat glands, the same type found in your armpits. These glands release a thick, oily sweat that is odorless on its own but becomes pungent when bacteria on the skin’s surface break it down. Tight clothing, exercise, warm weather, and synthetic underwear fabrics can all intensify this process.
Washing the vulva (the outer area) with warm water and wearing breathable, cotton underwear are the simplest ways to manage sweat-related odor. Scented soaps, douches, and vaginal deodorants can actually make things worse by disrupting the vagina’s natural bacterial balance and pH, setting the stage for infections that cause even stronger smells.
How Food and Diet Play a Role
Certain foods can temporarily change the way your body smells overall, including your vaginal scent. Garlic, onions, asparagus, Brussels sprouts, fish, coffee, red meat, and spicy foods have all been linked to shifts in body odor. Supplements containing choline can have a similar effect. Genetics influence how strongly any given food affects your scent, so the same meal might change things noticeably for one person and not at all for another.
These dietary effects are temporary and mild. If you notice a pattern between certain foods and an unwanted scent, cutting back is a simple fix. But food alone doesn’t explain a persistent or strong vaginal odor.
Signs That Point to a Problem
A mild or shifting scent on its own rarely indicates anything serious. The combination of odor with other symptoms is what matters. Pay attention if you notice:
- Greenish, yellowish, or thick, cheesy discharge
- Strong odor that doesn’t resolve after showering or changing underwear
- Itching, burning, or irritation of the vagina or vulva
- Color changes to vulvar skin, such as unusual redness or darkening
- Bleeding or spotting outside your normal period
Any of these alongside a noticeable smell suggests an infection or another condition that benefits from diagnosis and treatment. Most causes, including BV and trichomoniasis, are straightforward to treat once identified. A simple swab test is usually all that’s needed to pinpoint the cause.