What are the recommended treatments for bacterial vaginosis (BV) and fungal vaginosis in pregnancy?

Treatment of Bacterial and Fungal Vaginosis in Pregnancy

Bacterial Vaginosis Treatment

For pregnant women with bacterial vaginosis, use oral metronidazole 250 mg three times daily for 7 days starting in the second trimester, or clindamycin vaginal cream 2% if treatment is needed in the first trimester. 1, 2

First Trimester Approach

• Clindamycin vaginal cream 2% (one full applicator intravaginally at bedtime for 7 days) is the preferred first-line treatment if bacterial vaginosis requires treatment during the first trimester 1
• Oral metronidazole is traditionally avoided in the first trimester due to historical teratogenicity concerns, though multiple meta-analyses have not demonstrated consistent associations between metronidazole use and congenital anomalies 2
• Do not use metronidazole gel intravaginally during the first trimester - existing data do not support topical metronidazole agents during pregnancy 1

Second and Third Trimester Approach

• Oral metronidazole 250 mg three times daily for 7 days is the recommended regimen for both symptomatic and high-risk asymptomatic pregnant women 3, 2
• Alternative regimens include:
  • Metronidazole 2 g orally in a single dose 3
  • Clindamycin 300 mg orally twice daily for 7 days 3
  • Metronidazole gel 0.75% intravaginally twice daily for 5 days (for low-risk symptomatic women only) 3

Risk Stratification Matters

High-risk pregnant women (those with prior preterm delivery):

• Should be screened and treated at the first prenatal visit or earliest part of second trimester 3
• Treatment reduces preterm delivery in three of four randomized controlled trials 3, 2
• Require follow-up evaluation at 1 month after treatment completion to evaluate treatment success 3, 2

Low-risk pregnant women (no history of preterm delivery):

• Treat only if symptomatic to relieve symptoms 3
• Follow-up visits unnecessary if symptoms resolve 3, 2

Critical Safety Considerations

• Avoid clindamycin vaginal cream in later pregnancy - three randomized trials showed increased adverse events (prematurity and neonatal infections) after use, particularly in newborns 3, 1
• The 250 mg three times daily metronidazole regimen (lower than the 500 mg twice daily used in non-pregnant women) was specifically studied in pregnancy trials that demonstrated benefit and minimizes fetal exposure 3, 2
• Systemic therapy is preferred over topical therapy to treat possible subclinical upper genital tract infections 3, 1, 2

Important Clinical Pitfalls

• Do not treat male sex partners - clinical trials show this does not affect treatment response or reduce recurrence rates 3
• Patients allergic to oral metronidazole should NOT receive metronidazole gel vaginally 3, 1
• Patients should avoid alcohol during metronidazole treatment and for 24 hours thereafter due to potential disulfiram-like reaction 3
• Clindamycin cream is oil-based and may weaken latex condoms and diaphragms 3, 1

Rationale for Treatment

Bacterial vaginosis is associated with serious adverse pregnancy outcomes including:

• Premature rupture of membranes 3, 2
• Preterm labor and preterm birth 3, 2
• Chorioamnionitis 3, 2
• Postpartum endometritis and post-cesarean wound infections 3, 2

The relative risk of preterm delivery is 1.4-6.9, and the relative risk of preterm premature rupture of membranes is 2.0-7.3 2

Fungal Vaginosis (Vulvovaginal Candidiasis) Treatment

Note: The provided evidence does not contain specific guidelines for fungal vaginosis treatment during pregnancy. Based on general medical knowledge, topical azole antifungals (clotrimazole, miconazole) for 7 days are preferred during pregnancy, as oral fluconazole is generally avoided due to potential teratogenicity concerns at high doses. However, definitive recommendations require consultation of appropriate guidelines not included in this evidence set.