Screening for bacterial vaginosis in pregnancy: a meta-analysis

Abstract

Objective: To assess the value of screening for bacterial vaginosis (BV) in pregnancy.Methods: As part of a systematic evidence review of screening for BV, we performed a meta-analysis of randomized trials of BV treatment for women at average risk and high risk for preterm delivery. Treatment trials were included in the meta-analysis if they reported at least one pregnancy outcome. We applied a new graphical meta-analytic method to derive pooled estimates of the effect of treatment and to characterize and interpret conflicting results among randomized trials. Using this method, we examined the relationship between risk status and the efficacy of treatment, and estimated potential benefits and harms of screening in the general population and high-risk groups.Results: Eight randomized controlled trials met inclusion criteria for the meta-analysis. We found no benefit of BV treatment in average-risk women for any pregnancy outcome. Results of studies of high-risk populations were inconsistent and statistically heterogeneous. They were clustered into two groups, one showed potential benefit of BV treatment (effect size 0.23, CI 0.13–0.31), the other potential harm (−0.17, CI –0.2 ± 0.02) for preterm delivery before 37 weeks. Subgroup analysis suggests a subset of very high-risk women benefit from screening and treatment of BV.Conclusions: Randomized trials show no benefit to screening and treating all pregnant women for BV. There appears to be a subgroup of high-risk women that benefit from BV screening.