What is the recommended treatment for bacterial vaginosis (BV) in pregnant women?

Treatment of Bacterial Vaginosis in Pregnancy

For pregnant women with bacterial vaginosis, oral metronidazole 250 mg three times daily for 7 days is the recommended first-line treatment, with oral clindamycin 300 mg twice daily for 7 days as an acceptable alternative. 1, 2

Treatment Recommendations

First-line Options:

• Metronidazole 250 mg orally three times daily for 7 days 1
• Clindamycin 300 mg orally twice daily for 7 days 1

Important Considerations:

Symptomatic vs. Asymptomatic Treatment

• All symptomatic pregnant women should be tested and treated 1
• High-risk asymptomatic women (those with previous preterm delivery) should be screened and treated, preferably in the early second trimester 1
• Treatment of asymptomatic high-risk women has been shown to reduce preterm delivery in three of four randomized controlled trials 1

Medication Selection

• Systemic therapy is preferred over topical agents during pregnancy 1
• Topical agents are not recommended during pregnancy 1
  • Evidence from three trials suggests increased adverse events (prematurity and neonatal infections) with clindamycin cream 1
  • Data on metronidazole vaginal gel during pregnancy are limited 1

Treatment Algorithm

1. Determine risk status:

   • High-risk: Previous preterm delivery
   • Low-risk: No history of preterm delivery

2. For symptomatic women (regardless of risk status):

   • First choice: Metronidazole 250 mg orally three times daily for 7 days
   • Alternative: Clindamycin 300 mg orally twice daily for 7 days

3. For asymptomatic high-risk women:

   • Screen at first prenatal visit
   • If positive, treat with metronidazole 250 mg orally three times daily for 7 days

4. For asymptomatic low-risk women:

   • Routine screening and treatment are not clearly supported by evidence 1

Safety Considerations

• Multiple studies and meta-analyses have not demonstrated consistent associations between metronidazole use during pregnancy and teratogenic or mutagenic effects in newborns 1
• Lower doses of medication (250 mg three times daily rather than 500 mg twice daily) are recommended during pregnancy to minimize fetal exposure 1
• Patients should avoid alcohol during treatment with metronidazole and for 24 hours afterward 2

Follow-up

• A follow-up evaluation 1 month after completion of treatment should be considered for high-risk pregnant women to evaluate treatment effectiveness 1
• Treatment of male sex partners is not recommended as it does not affect the woman's response to therapy or likelihood of recurrence 1

Common Pitfalls to Avoid

• Avoid using clindamycin vaginal cream during pregnancy due to increased risk of adverse pregnancy outcomes 1
• Avoid single 2g dose metronidazole regimen during pregnancy, as trials using this regimen have shown it to be ineffective in reducing preterm birth 1
• Don't neglect follow-up in high-risk pregnant women, as treatment success is important for preventing adverse pregnancy outcomes 1
• Don't routinely treat partners, as this has not been shown to improve outcomes 1