Screening for Bacterial Vaginosis in Pregnancy

• The USPSTF recommends against screening for bacterial vaginosis in asymptomatic pregnant women at low risk for preterm delivery. (This is a grade "D" recommendation.)
• The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for bacterial vaginosis in asymptomatic pregnant women at high risk for preterm delivery. (This is an "I" statement.)

Rationale:

Importance

The associations between bacterial vaginosis and adverse pregnancy outcomes, such as preterm delivery, are well documented.

Detection

Good-quality evidence indicates that screening tests (the Amsel clinical criteria or Gram stain) can detect bacterial vaginosis.

Benefits of Detection and Early Intervention

Asymptomatic Pregnant Women at Low Risk for Preterm Delivery. No direct evidence indicates that screening for bacterial vaginosis reduces adverse health outcomes in asymptomatic pregnant women at low risk for preterm delivery. Good evidence indicates that treatment of bacterial vaginosis in these women lacks benefit.

Asymptomatic Pregnant Women at High Risk for Preterm Delivery. No direct evidence indicates that screening for bacterial vaginosis reduces adverse health outcomes in asymptomatic pregnant women at high risk for preterm delivery. Evidence from good-quality studies is conflicting with respect to the benefits of treating bacterial vaginosis.

Harms of Detection and Early Treatment

Asymptomatic Pregnant Women at Low Risk for Preterm Delivery. Evidence is poor (because studies are lacking) for harms of screening for bacterial vaginosis in asymptomatic pregnant women at low risk for preterm delivery. Evidence is fair that false-positive results from screening lead to harms due to treatment.

Asymptomatic Pregnant Women at High Risk for Preterm Delivery. Evidence is poor (because studies are lacking) for harms of screening for bacterial vaginosis in asymptomatic pregnant women at high risk for preterm delivery. Studies on the harms of treatment have conflicting results.

USPSTF Assessment. The USPSTF concludes that for asymptomatic pregnant women at low risk for preterm delivery, there is moderate certainty that screening for bacterial vaginosis has no net benefit.

The USPSTF concludes that for asymptomatic pregnant women at high risk for preterm delivery, the evidence is conflicting and the balance of benefits and harms cannot be determined.