Bacterial Vaginosis Prophylaxis
Routine prophylaxis for bacterial vaginosis is not recommended for most women; however, specific high-risk populations benefit from screening and treatment, including pregnant women with prior preterm delivery and women undergoing surgical abortion or hysterectomy. 1, 2
General Population: No Routine Prophylaxis
- Asymptomatic women without risk factors should not receive prophylactic treatment for BV. 2
- Treatment of male sex partners does not prevent BV recurrence and is not recommended as a prophylactic strategy. 1, 2, 3
- The CDC explicitly advises against treating asymptomatic women unnecessarily, except in specific high-risk situations. 2
High-Risk Populations Requiring Prophylaxis
Pregnant Women at High Risk for Preterm Delivery
- Pregnant women with a history of preterm delivery who have asymptomatic BV should be evaluated for treatment to reduce the risk of prematurity. 1, 2
- All symptomatic pregnant women with BV require treatment due to associations with premature rupture of membranes, preterm labor, preterm birth, and postpartum endometritis. 1, 2
Women Undergoing Invasive Gynecologic Procedures
- Screen and treat women with BV before surgical abortion or hysterectomy in addition to routine prophylaxis. 1
- Randomized controlled trials demonstrated that metronidazole treatment substantially reduced postabortion pelvic inflammatory disease. 1
- Studies showed a 10-75% reduction in postoperative infectious complications when anaerobic antimicrobial coverage was added before abortion or hysterectomy. 1
- More information is needed before recommending prophylactic treatment before other invasive procedures (endometrial biopsy, hysterosalpingography, IUD placement, cesarean section, uterine curettage). 1
Prophylactic Treatment Regimens When Indicated
When prophylaxis is warranted for high-risk populations, use standard treatment regimens:
- Metronidazole 500 mg orally twice daily for 7 days (first-line, 95% cure rate). 2, 3
- Alternative: Metronidazole gel 0.75% intravaginally once daily for 5 days. 1
- Alternative: Clindamycin cream 2% intravaginally at bedtime for 7 days. 1, 3
Important caveat: Patients must avoid alcohol during metronidazole treatment and for 24 hours afterward due to potential disulfiram-like reaction. 2, 3
Recurrent BV: Extended Prophylaxis
For women with recurrent BV (not primary prophylaxis), consider:
- Extended metronidazole therapy: 500 mg twice daily for 10-14 days. 4
- If ineffective, metronidazole vaginal gel 0.75% for 10 days, followed by twice weekly for 3-6 months. 4
- Adjunctive probiotics (Lactobacillus rhamnosus) after antibiotic therapy may reduce recurrence rates, with significantly lower recurrence at 6 and 9 months compared to antibiotics alone. 5, 6
Common Pitfalls to Avoid
- Do not treat asymptomatic low-risk women as this provides no benefit and contributes to antibiotic resistance. 2
- Do not treat male partners as prophylaxis—this strategy has been proven ineffective in multiple trials. 1, 2, 3
- Do not rely on single-dose metronidazole 2g for prophylaxis, as it has lower efficacy than the 7-day regimen. 1
- Remember that up to 50-80% of women experience BV recurrence within one year despite appropriate treatment, so counsel patients accordingly. 4, 7