Bacterial Vaginosis

Bacterial vaginosis (BV) results from an overgrowth of anaerobic bacteria — displacing the normal Lactobacillus-dominant vaginal flora. It causes a thin, gray-white, fishy-smelling discharge — particularly noticeable after intercourse. It is not a sexually transmitted infection in the traditional sense, though sexual activity influences vaginal flora.

BV produces thin, gray-white discharge with a fishy odor and minimal itching. Vaginal yeast infection causes thick, white, cottage cheese-like discharge with significant vulvar itching and burning — without odor. Clinical evaluation or vaginal pH testing distinguishes them. Both are common and have different treatments.

Symptomatic BV should be treated — it is associated with increased susceptibility to STIs and adverse pregnancy outcomes. Asymptomatic BV may not require treatment in non-pregnant women who don't have symptoms, though some clinicians treat to restore normal flora. In pregnancy, treatment is recommended regardless of symptoms.

BV recurrence rates are high — approximately 50–70% within 6–12 months of treatment. Recurrence reflects re-establishment of the bacterial imbalance rather than treatment failure. Strategies to reduce recurrence include prolonged or suppressive metronidazole use, boric acid vaginal suppositories, and avoiding douching and alkaline products.

Metronidazole gel is very well tolerated locally. Oral metronidazole causes nausea, metallic taste, and GI upset — alcohol must be avoided during treatment and for 24 hours after. Clindamycin vaginal cream may cause vaginal irritation and may weaken latex condoms. Boric acid suppositories are safe vaginally — never to be taken orally.