1. Purpose of treatment: Treatment can relieve vaginal signs and symptoms, reduce the risk of BV-related infectious complications during pregnancy, reduce the risk of preterm delivery or low birth weight babies, and reduce the risk of infectious complications after miscarriage or hysterectomy, etc. Although treatment can achieve a cure rate of over 80%, there can be an 80% recurrence rate within 1 year. 2. Treatment regimen: (1) Recommended regimen: ①Metronidazole 400-500mg, orally, 2 times/d, for 7 days. (2) 0.75% metronidazole gel 5g, administered intravaginally, once a night, for 5 days. ③2％ clindamycin cream 5g, administered intravaginally once a night for 7 days. (2) Alternative regimen: ①Metronidazole 2g, once in a single dose. ②Clindamycin 300mg, orally, 2 times/d, for 7 days. (3) Treatment plan for pregnant women: ①Metronidazole 200mg orally 3 times/d for 7 days. (2) Clindamycin 300mg, orally, 2 times/d, for 7 days. 3. Precautions (1) Alcohol should be avoided during metronidazole treatment and for 48 h after treatment to prevent withdrawal sulfur-like reactions. treatment with other drugs (e.g. clindamycin) can be switched in case of BV relapse. (2) Although the available data do not find any association between the use of metronidazole in pregnancy and neonatal teratogenicity, metronidazole should be used with caution in early pregnancy, and intravaginal topical treatment is preferable for lactating women. (3) Treatment of male sexual partners does not improve the clinical outcome of BV or reduce recurrence. Therefore, routine treatment of male sexual partners is not advocated.