Bacterial vaginosis (BV) — what to know and what to do
BV is the most common vaginal infection in people of childbearing age. It happens when the normal balance of bacteria in the vagina shifts and anaerobic bacteria grow too much. That imbalance causes symptoms many find upsetting: unusual discharge, a thin gray or white texture, and a fishy odor that can get stronger after sex.
Symptoms & diagnosis
Wondering how to tell BV from yeast or other infections? Look for these signs: a thin gray or white discharge, a strong fishy smell (especially after sex), and mild irritation or burning. BV usually does not cause fever or severe pain. If you have pelvic pain, fever, or heavy bleeding, get medical help.
Clinicians use a quick bedside check: they look at discharge under a microscope for "clue cells," test the vaginal pH (often above 4.5 with BV), and may do a whiff test with a drop of KOH to detect the fishy odor. Lab tests can confirm the diagnosis if needed.
Treatment and prevention
First-line treatment usually means antibiotics your clinician prescribes: oral metronidazole or a topical metronidazole gel, and sometimes topical clindamycin. These medicines work well for many people and usually clear symptoms in a few days. Always finish the full course even if you feel better early.
Recurrent BV is common. If it keeps coming back, your clinician may suggest a longer antibiotic course or repeated short courses. Avoid using antibiotics without a prescription — they can make the balance worse if used incorrectly.
Want to reduce your chance of BV? Simple habits help: avoid douching (it disrupts normal bacteria), limit scented products in the genital area, and use condoms if you have new or multiple partners. Switching or stopping certain types of intra-vaginal products can also help. Evidence for probiotics is mixed — some people get benefit but it's not guaranteed, so talk to your clinician before trying them.
When should you see a clinician? If you think you have BV and symptoms are new or bothersome, get checked. Also seek care if you are pregnant — BV can raise certain pregnancy risks and often needs treatment. If symptoms return within a month of treatment, see your clinician again for re-evaluation.
Curious about the antibiotics used for infections? Read our related guides on tetracycline and ofloxacin to learn how different antibiotics work and why you should only take drugs your clinician prescribes. If cost or access to prescriptions is a worry, check our articles on safe online pharmacies and discount options.
Have questions or unclear symptoms? Reach out to a clinician — BV is common and treatable, and getting the right diagnosis makes a quick difference.