Why Do I Have a Persistent, Fishy Odor in My Groin Area?

A persistent fishy odor in the groin area can be uncomfortable and embarrassing, but it is not something you need to ignore or simply cover with fragrance. The odor may come from sweat and bacteria on the skin, moisture trapped in clothing, a vaginal bacterial imbalance, an infection, or another condition that requires an examination.

The location of the odor matters. An odor coming primarily from the skin folds may have different causes than one accompanied by vaginal discharge, urinary symptoms, sores, or irritation. Because several conditions can produce similar symptoms, an in-person evaluation is often the clearest way to identify the source.

Quick answer

• Sweat does not have a strong odor by itself, but skin bacteria can break it down and create a noticeable smell.
• A fish-like vaginal odor can be associated with bacterial vaginosis, especially when there is thin gray or white discharge.
• Trichomoniasis and other infections may also cause unusual odor, irritation, discomfort, or changes in discharge.
• A retained tampon or another foreign object can cause a persistent, unpleasant vaginal odor.
• Odor that continues despite gentle hygiene, or occurs with pain, discharge, sores, fever, or urinary symptoms, should be evaluated by a healthcare professional.

Where is the odor coming from?

The groin contains warm skin folds, hair follicles, sweat glands, genital tissue, and areas where moisture can become trapped. Odor may originate from the outer skin, the vagina, urine, a wound, or discharge from an infection. Pinpointing the source helps a clinician determine which examination or tests may be useful.

In women, odor may come from the external groin skin, vulva, vagina, urine, or a draining skin lesion. A dermatologist is the appropriate specialist when the problem appears to involve the external skin, such as a rash, irritation, sweating, recurrent boils, cysts, or drainage. When the odor appears vaginal or occurs with unusual discharge, pelvic discomfort, pain with sex, or a possible retained tampon, an obstetrician-gynecologist or primary care clinician is usually the better first appointment. Burning with urination, urinary urgency, or suspected urine leakage may also be evaluated by a primary care clinician, gynecologist, or urologist, depending on the symptoms.

Common causes of a persistent fishy groin odor

Sweat and skin bacteria

The groin contains apocrine sweat glands. When sweat, oils, dead skin cells, and naturally present bacteria interact, they can create a strong odor. Hot weather, exercise, stress, tight clothing, and remaining in damp underwear or swimwear can make the smell more noticeable.

Bacterial vaginosis

Bacterial vaginosis, often called BV, occurs when the usual balance of bacteria in the vagina changes. It can be associated with a strong fish-like odor, sometimes more noticeable after sex, along with thin white or gray discharge. Some people have few additional symptoms. BV cannot be confirmed by odor alone, so testing may be needed.

Trichomoniasis or another sexually transmitted infection

Trichomoniasis is a sexually transmitted infection that may cause an unpleasant vaginal odor, irritation, discomfort with urination or sex, and yellow-green or frothy discharge. Other sexually transmitted infections may produce overlapping symptoms or no obvious symptoms at all. A clinician can recommend appropriate testing based on your symptoms and history.

A retained tampon or foreign object

A forgotten tampon or another retained object may cause a strong, persistent vaginal odor and unusual discharge. Do not repeatedly insert tools or attempt aggressive removal. Seek prompt medical care if you cannot easily remove the object or are uncertain whether something remains inside.

Moisture-related skin irritation or infection

Friction and trapped moisture can weaken the skin barrier and contribute to irritation in the inner thighs, beneath the abdomen, around the genitals, or between the buttocks. Bacterial or fungal overgrowth may occur in these areas. Clues can include redness, scaling, tenderness, cracking, itching, drainage, or a sharply bordered rash.

Urine, discharge, or leakage

Small amounts of urine, vaginal discharge, semen, or stool can remain on the skin or clothing and alter the odor of the groin. Urinary leakage, concentrated urine, or a urinary problem may be mistaken for skin odor. The accompanying symptoms often help identify the source.

Less common causes

More unusual causes can include an abscess, draining cyst, wound, fistula, or another medical condition. These possibilities are less common, but they are important to consider when odor is persistent, suddenly different, or accompanied by visible skin changes, drainage, bleeding, or systemic symptoms.

What you can do at home

• Wash the external groin gently with lukewarm water and a mild, fragrance-free cleanser.
• Dry skin folds thoroughly by patting rather than rubbing.
• Change promptly after exercising, swimming, or sweating heavily.
• Wear breathable underwear and avoid clothing that repeatedly traps heat and moisture.
• Wash underwear, workout clothes, towels, and swimwear after use.
• Avoid douching, vaginal deodorants, fragranced wipes, perfumes, and harsh antiseptics.
• Do not apply leftover antibiotics, antifungal creams, or steroid creams unless a clinician has recommended them for the current problem.
• Pause shaving or waxing if the skin is inflamed, broken, or covered with painful bumps.

These steps may reduce odor related to moisture or surface bacteria, but they will not address every possible cause. A persistent fishy smell should not be repeatedly masked with scented products because irritation can worsen and the underlying issue may remain untreated.

How a clinician may evaluate the odor

A dermatologist may ask when the odor began, where it seems strongest, whether it changes after exercise, and whether there is itching, redness, scaling, tenderness, bumps, drainage, or an open sore. The external groin skin may be examined for moisture-related irritation, bacterial or fungal overgrowth, inflamed hair follicles, cysts, abscesses, wounds, or other skin conditions.

If the symptoms suggest that the odor is coming from the vagina rather than the external skin, the dermatologist may recommend evaluation by an obstetrician-gynecologist or primary care clinician. That evaluation may include a pelvic examination, a sample of vaginal discharge, sexually transmitted infection testing, or a urine test. A dermatologist may swab drainage or affected external skin when a bacterial or fungal skin condition is suspected. Treatment depends on the identified cause and may involve prescription medication, moisture and sweating control, or treatment of an underlying skin disorder.

When to seek medical care

Arrange an appointment when the odor is new, persistent, frequently returns, or does not improve with gentle hygiene and dry clothing. Choose the clinician based on where the symptoms appear to originate: see a dermatologist for an external groin rash, skin irritation, recurrent boils, cysts, sweating, or drainage; see an obstetrician-gynecologist or primary care clinician for vaginal odor or discharge, pelvic symptoms, possible sexually transmitted infection exposure, or a possible retained tampon; and seek primary care evaluation for urinary burning, urgency, or suspected urine leakage. Seek care sooner if you notice:

• New or unusual vaginal or penile discharge
• Burning with urination
• Pelvic, genital, or lower abdominal pain
• Significant itching, swelling, redness, or tenderness
• Sores, blisters, ulcers, or a spreading rash
• A painful lump, pus, drainage, or an open wound
• Bleeding that is not expected
• Fever, chills, vomiting, dizziness, or feeling seriously unwell
• A possible retained tampon or other object
• Symptoms during pregnancy
• A recent new sexual partner or possible exposure to an infection

Severe pain, rapidly spreading redness, high fever, fainting, confusion, or feeling acutely ill warrants urgent medical attention.

Frequently asked questions

Does a fishy odor always mean bacterial vaginosis?

No. BV is one possible cause, particularly when the odor comes from the vagina, but sweat, skin bacteria, trichomoniasis, a retained tampon, and other conditions can also cause unusual odor. Testing may be needed to distinguish them.

Can a yeast infection cause a fishy smell?

Yeast infections more commonly cause itching, irritation, and thick white discharge than a strong fish-like odor. Because symptoms can overlap, avoid assuming the cause based only on smell.

Can a dermatologist diagnose bacterial vaginosis?

A dermatologist can determine whether an external skin condition is contributing to odor, irritation, rash, cysts, or drainage. Bacterial vaginosis is a vaginal condition and is generally diagnosed through an evaluation by an obstetrician-gynecologist, primary care clinician, or sexual health provider, often with testing of vaginal fluid.

Should I use an intimate wash or deodorizing spray?

Fragranced washes, deodorants, sprays, and wipes can irritate sensitive genital skin and disrupt the vaginal environment. Use a mild, fragrance-free cleanser only on external skin and avoid placing cleansing products inside the vagina.

Can hot Florida weather make groin odor worse?

Heat and humidity can increase sweating and keep skin folds damp for longer periods. Breathable clothing, changing after sweating, and drying the area carefully may help reduce moisture-related odor.

Which type of healthcare professional should I see?

See a dermatologist when the concern involves the external groin skin, including a rash, chafing, persistent irritation, excessive sweating, recurrent boils, cysts, wounds, or drainage. See an obstetrician-gynecologist or primary care clinician when the odor appears to come from the vagina or is accompanied by unusual discharge, pelvic pain, pain with sex, pregnancy, a possible retained tampon, or concern about a sexually transmitted infection. Urinary burning, urgency, or leakage can begin with a primary care clinician and may require gynecologic or urologic follow-up.

This article is for educational purposes and is not medical advice. A board-certified dermatologist can evaluate symptoms involving the external groin skin. Vaginal, pelvic, urinary, pregnancy-related, or sexually transmitted infection concerns may require evaluation by an obstetrician-gynecologist, primary care clinician, sexual health provider, or other appropriate medical professional.

Sources & further reading

• Centers for Disease Control and Prevention (CDC) – About Bacterial Vaginosis
• Mayo Clinic – Vaginal Odor Causes
• Cleveland Clinic – Body Odor: Causes, Changes, Underlying Diseases and Treatment