Bacterial vaginosis (BV) is an imbalance in which normal protective lactobacilli in the vagina are replaced by an overgrowth of other bacteria. It often causes a thin, gray-white discharge with a fishy odor, especially after sex, but many women have no symptoms. BV is diagnosed with a simple swab and treated with prescription antibiotics, though it often comes back.
- Cause
- Imbalance of vaginal bacteria
- Main symptoms
- Thin discharge, fishy odor
- Diagnosis
- Exam, pH and swab microscopy
- Treatment
- Oral or vaginal antibiotics
- Recurrence
- Common within months
- Cost guide
- Consult + tests ~₩30,000–100,000
What is bacterial vaginosis?
A healthy vagina is usually dominated by lactobacilli, bacteria that keep the environment slightly acidic. In bacterial vaginosis, these decrease and other bacteria such as Gardnerella increase, raising the vaginal pH. BV is the most common cause of abnormal discharge in women of reproductive age.
BV is not considered a sexually transmitted infection, but it is more common with a new partner or multiple partners and in women who douche. It cannot be caught from toilet seats or swimming pools. Because its symptoms overlap with STIs, it is often checked alongside them — see vaginal infections for a comparison.
BV symptoms and how it differs from other infections
Up to half of women with BV notice no symptoms. When present, they usually include a thin, watery gray or white discharge and a fishy odor that may be stronger after sex or during a period. Itching and soreness are less typical.
| Bacterial vaginosis | Yeast infection | Trichomoniasis | |
|---|---|---|---|
| Discharge | Thin, gray-white | Thick, white, curd-like | Frothy, yellow-green |
| Odor | Fishy | Usually none | Often unpleasant |
| Itching | Mild or none | Often strong | Common |
| Sexually transmitted? | No, but linked to sex | No | Yes |
| Treatment | Antibiotics | Antifungals | Antiparasitic medication |
Because symptoms overlap, self-treating with over-the-counter yeast products often does not help BV. Read more about yeast infections and trichomoniasis.
How BV is diagnosed at Yoonho
- Consultation in English Your doctor asks about discharge, odor, timing, previous episodes, partners and any products used.
- Gentle speculum exam The discharge is looked at and a small swab is taken. It takes a few minutes.
- pH and microscopy Vaginal pH and a microscope check for typical "clue cells" can often confirm BV at the same visit.
- STI tests if appropriate If you have a new partner or other risk factors, chlamydia, gonorrhea and trichomonas tests may be added — see the STD test panel.
- Treatment plan You leave with a prescription and written instructions, and a follow-up is arranged if symptoms persist.
- Thin gray-white discharge
- Fishy odor, often after sex
- Higher vaginal pH
- Repeated episodes
- Aims to restore normal discharge
- Odor usually settles within days
- Plan to reduce recurrence
- Many patients notice relief
Treatment options and recurrence
BV that causes symptoms is treated with prescription antibiotics, commonly metronidazole tablets or vaginal gel, or clindamycin vaginal cream, usually for 5–7 days. Your doctor chooses based on pregnancy, breastfeeding, allergies and preference.
- Finish the full course even if symptoms improve.
- Your doctor will advise whether to avoid alcohol with your medication.
- Clindamycin cream can weaken latex condoms for several days.
Recurrence is common — many women have BV again within a year. For frequent episodes, options include a longer suppressive course, reviewing triggers such as douching, and in some cases discussing partner treatment, which recent research suggests may help some couples.
Why treating BV matters — and prevention
BV is not dangerous in most cases, but it is linked to a higher risk of acquiring STIs including HIV, to infection after gynecologic procedures, and, in pregnancy, to preterm birth. If you are pregnant or planning a procedure such as IUD insertion, tell your doctor about symptoms.
- Avoid douching and scented washes inside the vagina; warm water externally is enough.
- Use condoms with new partners.
- Wear breathable cotton underwear and change out of damp clothing.
Cost and documents for international patients
As a general guide, a consultation with tests is about ₩30,000–100,000 and medication about ₩10,000–50,000; a written estimate is given after consultation if extra tests are added. Residents enrolled in National Health Insurance are usually covered for diagnosis and treatment. English receipts and diagnosis notes are available for travel insurance claims.
Why international patients choose Yoonho
Frequently asked questions
Is bacterial vaginosis an STD?
No. BV is a bacterial imbalance, not a classic sexually transmitted infection, but it is more common with new or multiple partners. Your doctor may still suggest STI tests if you have risk factors.
Does my partner need treatment?
Routine treatment of male partners has not traditionally been recommended. Recent studies suggest partner treatment may reduce recurrence in some couples, so ask your doctor if BV keeps coming back. Female partners may also have BV and can be checked.
Can BV go away on its own?
Sometimes it does, but symptomatic BV is usually treated because treatment relieves symptoms faster and reduces related risks, especially in pregnancy.
Can I buy BV treatment at a Korean pharmacy?
BV antibiotics such as metronidazole require a prescription in Korea. Over-the-counter yeast treatments do not treat BV.
Can I have sex during treatment?
It is generally advised to avoid sex until you finish treatment and symptoms resolve. Note that clindamycin cream can weaken latex condoms.
OB-GYN Specialist · Director of OB-GYN
M.D., Ewha Womans University College of Medicine · Former Clinical Instructor, Ewha Womans University Mokdong Hospital · Member, Korean Society of Menopause
Last reviewed: . This page is for general information and does not replace an in-person consultation.
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