Cost-effectiveness of screening and treatment for bacterial vaginosis in early pregnancy among women at low risk for preterm birth.

Abstract

Bacterial vaginosis (BV) is an important risk factor for preterm birth. BV is detected in 10-30% of pregnant women and is often asymptomatic. Treatment of BV during pregnancy seems to reduce the risk of preterm delivery among high-risk women. We performed a cost-effectiveness analysis of screening and treatment for BV in early pregnancy among asymptomatic women at low risk for preterm delivery. A decision tree was built with two arms. For the screening (and treatment) arm the probabilities were derived from our earlier randomized trial on screening and treatment for BV, consisting of BV-positive women treated with intravaginal clindamycin cream or placebo and also of BV-negative pregnant women. The probabilities of outcomes among these women were collected from antenatal clinic records and hospital records, and for the no-screening arm mainly from the Finnish Perinatal Statistics. The outcomes considered were preterm delivery, mode of delivery, peripartum infections and postpartum complications. The unit costs associated with these outcomes were mainly based on disease-related groups (DRGs). No-screening was compared with two screening programs (one with clindamycin, the other with metronidazole treatment) and subjected to sensitivity analyses. There was no significant difference between screening and no-screening strategies in the costs and in the rate of preterm deliveries but the screening strategy produced significantly fewer peripartum infections and postpartum complications. Sensitivity analyses suggested that the screening strategy may become cost-saving if the rate of preterm deliveries exceeds 3%. Screening and treatment for BV in early pregnancy may not reduce costs compared to no-screening in a population at low risk for preterm birth but would produce, at the same cost, more health benefits in terms of fewer peripartum infections and postpartum complications. However, it may be cost-saving if the rate of preterm deliveries is higher than 3%.