Bacterial vaginosis (BV) develops when the balance of bacteria in the vagina shifts. It is not caused by poor hygiene, and a doctor can treat it with antibiotics.
What it is
BV is an imbalance of vaginal bacteria, where Gardnerella and others outgrow lactobacilli. It is the most common vaginal condition in women aged 15 to 44.
Risk factors
- New or multiple sexual partners.
- Douching.
- Smoking.
- IUD.
Is it an STI
No, but sex can raise risk.
Symptoms
Thin gray discharge, fishy smell, itching. Many have none.
Treatment
Antibiotics, such as metronidazole.
Prevention
Avoid douching.
Condition
Bacterial vaginosis (BV) is an imbalance of the vaginal bacteria, where normally dominant Lactobacillus decreases and other bacteria such as Gardnerella vaginalis overgrow. It is the most common vaginal condition in women aged 15 to 44. In the US, about 29% of women aged 14 to 49 have BV, according to the CDC.
Is it an STI
BV is not classified as a sexually transmitted infection, but it’s associated with sexual activity. It is more common in women with new or multiple partners and women who have sex with women, and it’s rare in people who have never been sexually active.
Risk factors
- Douching.
- New or multiple sex partners.
- Smoking.
- Intrauterine devices (IUDs), in some studies.
- Lack of lactobacilli.
- Hormonal changes.
- Black race, with higher prevalence linked to social and biological factors.
Symptoms
Thin gray or white discharge, a fishy odor (especially after sex) and sometimes itching or burning. About 50% to 75% of women have no symptoms.
Complications
Increased risk of acquiring HIV and other STIs, pelvic inflammatory disease, preterm birth and low birth weight when pregnant.
Diagnosis
Healthcare providers check vaginal pH (above 4.5), perform a wet mount microscopy or Gram stain, and look for clue cells.
Treatment
Antibiotics such as metronidazole (oral or gel), clindamycin cream or tinidazole. Recurrence is common, up to 50% within a year.
Prevention
Avoid douching, use condoms, limit partners, avoid scented soaps and wear cotton underwear. Probiotics have limited evidence.
See a provider
Do not self treat discharge with yeast infection medicines unless you know the cause.
Prevalence and cause
Bacterial vaginosis (BV) is the most common vaginal condition in women aged 15 to 44, and the CDC reported that about 29 percent of US women aged 14 to 49 had it in national survey data. It occurs when the balance of vaginal bacteria shifts, with fewer protective Lactobacillus species and more anaerobic bacteria. It is not strictly a sexually transmitted infection, but it is associated with new or multiple partners, and women who have sex with women are at higher risk. Douching, smoking and lack of condom use are other risk factors. Many cases have no symptoms.
Symptoms and treatment
Symptoms include a thin gray or white discharge and a fishy odor, especially after sex. Untreated BV can raise the risk of preterm birth and of acquiring STIs, including HIV. Diagnosis is by examination and testing of vaginal fluid. Treatment is with metronidazole or clindamycin by mouth or vaginal gel, and recurrence is common, occurring in up to half of women within a year. Avoid douching, use mild unscented soap and see a clinician for symptoms, especially during pregnancy.
Based on data from the CDC and ACOG
