What is the recommended treatment for bacterial vaginosis (BV) diagnosed during the second trimester of pregnancy?

Treatment of Bacterial Vaginosis in Second Trimester of Pregnancy

For bacterial vaginosis diagnosed during the second trimester of pregnancy, oral metronidazole 250 mg three times daily for 7 days is the recommended treatment. 1, 2

First-Line Treatment Options

• Metronidazole 250 mg orally three times daily for 7 days is the preferred treatment for BV during the second trimester of pregnancy 3, 1
• Alternative regimen: Clindamycin 300 mg orally twice daily for 7 days 3, 1

Rationale for Treatment

• BV during pregnancy is associated with adverse outcomes including premature rupture of membranes, preterm labor, preterm delivery, and postpartum infections 3, 1
• Systemic therapy is preferred over topical therapy during pregnancy to treat possible subclinical upper genital tract infections 3
• Treatment of BV in pregnant women has been shown to reduce the risk of preterm delivery in high-risk women (those with history of preterm birth) 3, 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 3, 1
• Clindamycin vaginal cream is not recommended during pregnancy due to evidence suggesting increased risk of adverse events (prematurity and neonatal infections) 3
• Patients using metronidazole should avoid alcohol during treatment and for 24 hours afterward due to potential disulfiram-like reaction 1, 2

Special Considerations for High-Risk Pregnant Women

• For women with a history of preterm delivery, screening and treatment should be performed at the first prenatal visit 3
• Treatment of asymptomatic BV in high-risk pregnant women may reduce the risk of preterm delivery 3, 1
• A follow-up evaluation one month after completion of treatment should be considered to evaluate whether therapy was effective in high-risk pregnant women 3

Management of Sex Partners

• Routine treatment of male sex partners is not recommended as it has not been shown to influence a woman's response to therapy or reduce recurrence rates 3, 2

Follow-Up

• Follow-up visits are not necessary if symptoms resolve 3, 2
• Recurrence of BV is common, and the alternative treatment regimens suitable for BV treatment may be used for treatment of recurrent disease 3

Treatment Algorithm

1. Confirm diagnosis of BV during second trimester
2. Assess risk factors for preterm delivery (history of previous preterm birth)
3. Initiate treatment with metronidazole 250 mg orally three times daily for 7 days 3, 1
4. If patient has allergy or intolerance to metronidazole, use clindamycin 300 mg orally twice daily for 7 days 3, 1
5. Counsel patient to avoid alcohol during treatment and for 24 hours afterward 1, 2
6. For high-risk women, consider follow-up evaluation one month after treatment completion 3

This evidence-based approach prioritizes maternal and fetal health outcomes while effectively treating the bacterial vaginosis infection during the second trimester of pregnancy.