You noticed a change down there: a thin grayish discharge, maybe a faint fishy smell that gets stronger after sex. It is uncomfortable, a little alarming, and you are not sure if it is a yeast infection, something you caught, or nothing at all. If this sounds familiar, you may be dealing with bacterial vaginosis, the most common vaginal condition in women of reproductive age and one that is very treatable.
Here is the reassuring part: bacterial vaginosis (BV) is extremely common, it is not a reflection of poor hygiene, and it responds well to a simple course of treatment from a clinician. Below we walk through exactly what BV symptoms look like, how they differ from a yeast infection, and when you should reach out for care.
What are the symptoms of bacterial vaginosis?
Bacterial vaginosis happens when the balance of bacteria naturally living in the vagina shifts, with a drop in protective Lactobacillus species and an overgrowth of other anaerobic bacteria. When BV does cause noticeable symptoms, the most common signs, according to the CDC, are:
- A thin white or gray vaginal discharge
- A strong fish-like odor, often more noticeable after sex
- Vaginal pain, itching, or burning
- Burning during urination
- Itching around the outside of the vagina
Can you have BV without any symptoms?
Yes, and this surprises many people. The large majority of BV cases are silent. In a national US study, only about 15.7% of women found to have BV reported any vaginal symptoms, meaning roughly 84% had no noticeable signs at all. So you can absolutely have BV without the classic discharge or odor.
This is part of why BV is so common overall. That same research estimated BV prevalence among US women at 29.2%, which works out to roughly 21 million women. Prevalence also varies by group, ranging from 23.2% in non-Hispanic White women to 31.9% in Mexican American women and 51.4% in non-Hispanic Black women. Because symptoms are often absent, a clinician's diagnosis matters more than self-assessment.
BV vs. a yeast infection: how to tell the difference
BV and yeast infections are both common, but they tend to feel different. The biggest clue is the odor and the look of the discharge.
BV usually brings a thin, grayish-white discharge with a distinct fishy smell, especially after sex. A yeast infection more typically causes thick, white, odorless discharge (often compared to cottage cheese) along with intense itching. Burning and irritation can show up with either, which is exactly why guessing wrong is easy. Because the treatments are completely different, an actual diagnosis is the safest path rather than reaching for an over-the-counter antifungal and hoping.
What causes BV and who is at risk?
BV is not caused by catching a single germ. It results from an overgrowth of bacteria that already live in the vagina, which upsets the natural balance. It is considered the most common vaginal condition in women ages 15 to 44, and it rarely affects people who have never had sex.
Certain factors raise the risk, including douching, inconsistent condom use, and having multiple or new sexual partners. Importantly, BV is not a sign of being unclean. In fact, douching, often done in the name of cleanliness, can make BV more likely by disrupting the vagina's natural environment. The vagina is self-cleaning and does not need internal washing.
How is BV diagnosed and treated?
A clinician diagnoses BV using established criteria. The Amsel clinical criteria require at least 3 of 4 findings: a thin homogeneous discharge, vaginal pH above 4.5, a positive whiff (amine) test when potassium hydroxide is added, and clue cells seen on microscopy. A lab method called the Nugent score is considered the gold standard.
BV is treated with prescription antibiotics, available as oral or topical regimens. It is worth knowing that BV commonly comes back. More than half of women experience a recurrence within 12 months of treatment, so if symptoms return, that does not mean you did anything wrong. It simply means it is worth checking in with a clinician again. Never share or reuse leftover prescriptions, and follow your clinician's specific instructions on any medication.
When should you see a doctor?
Reach out to a clinician whenever you have new or persistent vaginal discharge, odor, itching, or burning, particularly if this is your first time experiencing these symptoms, if you are pregnant, or if symptoms keep returning. Getting an accurate diagnosis matters because the right treatment depends on the cause.
Treating BV is not only about comfort. Untreated BV can increase the risk of acquiring or transmitting HIV and other sexually transmitted infections such as chlamydia and gonorrhea. During pregnancy, untreated BV raises the risk of premature delivery and low birth weight (under 5.5 pounds). Seek prompt medical care if you also have fever, pelvic or lower abdominal pain, or symptoms that are severe or rapidly worsening, as these can signal a more serious infection.
Medical Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider before starting any new skincare treatment, especially if you have underlying health conditions, are pregnant, or are taking medications.
