What is the treatment for bacterial vaginosis (BV)?

Bacterial Vaginosis Treatment

The CDC recommends metronidazole 500 mg orally twice daily for 7 days as first-line treatment for bacterial vaginosis, achieving a 95% cure rate. 1

Diagnosis

Bacterial vaginosis requires at least 3 of 4 Amsel's criteria: 1

• Homogeneous white non-inflammatory vaginal discharge
• Clue cells on microscopy
• Vaginal pH >4.5
• Positive whiff test (fishy odor with 10% KOH)

Alternatively, diagnosis can be made by Gram stain with Nugent score ≥4. 1

First-Line Treatment Options

Choose any of these CDC-recommended regimens: 1

Oral therapy:

• Metronidazole 500 mg orally twice daily for 7 days (95% cure rate)

Intravaginal therapy (alternative first-line):

• Metronidazole gel 0.75% intravaginally twice daily for 5 days (78-84% cure rate) 1
• Clindamycin cream 2% intravaginally at bedtime for 7 days (78-84% cure rate) 1

Second-Line Treatment

If first-line options fail or are not tolerated: 1

• Clindamycin 300 mg orally twice daily for 7 days
• Tinidazole 2g once daily for 2 days or 1g once daily for 5 days (therapeutic cure rates 22-32% above placebo) 2

Avoid single-dose metronidazole 2g as first-line therapy due to lower efficacy compared to the 7-day regimen. 1

Critical Safety Warnings

Patients must avoid all alcohol during metronidazole or tinidazole treatment and for 24 hours after completion to prevent disulfiram-like reactions. 1, 3

Clindamycin cream is oil-based and weakens latex condoms and diaphragms—counsel patients to use alternative contraception during treatment. 1, 3

Pregnancy Considerations

All symptomatic pregnant women require treatment due to associations with preterm birth, premature rupture of membranes, preterm labor, and postpartum endometritis. 1, 4

Treatment timing: 1

• Administer in second trimester (13-24 weeks)
• Use oral metronidazole (systemic therapy preferred for possible subclinical upper tract infection)

High-risk pregnant women (history of preterm delivery) with asymptomatic BV should be evaluated and treated to reduce prematurity risk. 1, 4

Follow-up evaluation at 1 month after treatment completion is recommended for high-risk pregnant women to verify cure. 1, 3

Recurrent Bacterial Vaginosis

Recurrence occurs in 50-80% of women within 1 year after standard treatment. 1, 5

For recurrent disease, use extended metronidazole treatment for 10-14 days, or metronidazole gel as suppressive therapy twice weekly for 3-6 months. 1, 5

Any alternative first-line regimen may also be used for recurrent disease. 1

Partner Treatment

Do NOT routinely treat male sex partners—multiple randomized controlled trials demonstrate this does not prevent recurrence or alter clinical outcomes in women. 1, 4

However, for women with recurrent BV, consider treating male partners with metronidazole 400 mg orally twice daily for 7 days plus 2% clindamycin cream applied to penile skin twice daily for 7 days, with both partners refraining from unprotected intercourse for at least 14 days. 3

Pre-Procedural Screening and Treatment

Screen and treat all women undergoing surgical abortion or hysterectomy before the procedure—treatment reduces postabortion pelvic inflammatory disease and postoperative infectious complications by 10-75%. 1, 4

Follow-Up

Routine follow-up visits are unnecessary if symptoms resolve. 1

Patients should return only if symptoms persist or recur after treatment. 3