Screening and treatment of bacterial vaginosis during pregnancy: a model for determining benefit

Bacterial vaginosis is associated with an increased risk of preterm birth. The treatment of bacterial vaginosis has recently been shown to decrease the risk of preterm delivery, especially in high-risk populations. However, the benefit of routine screening and treatment in the general population is uncertain. Using the information from several recent studies, a graph and nomogram generated from a mathematical model allow the obstetrician to determine the benefit of routine screening and treatment of bacterial vaginosis in his or her obstetrical population, depending on the prevalence of bacterial vaginosis and the total preterm delivery rate in that obstetrician's practice. If the prevalence of bacterial vaginosis and the incidence of preterm delivery are low, then routine screening would be expected to prevent small numbers of preterm births, and therefore may not be cost-effective.