News: Don't screen low-risk pregnant women for bacterial vaginosis

May 1, 2008

Do not screen pregnant women who are at low risk for preterm delivery for bacterial vaginosis (BV).

Do not screen pregnant women who are at low risk for preterm delivery for bacterial vaginosis (BV), says a recent update to the 2001 US Preventive Services Task Force Recommendation Statement.

After performing a series of meta-analyses on seven randomized controlled treatment trials published since the 2001 report, along with the data used in the 2001 report, the consensus is now that no benefit exists to screening or treating pregnant women for asymptomatic BV if they are at low- or average-risk for preterm premature rupture of membranes (PPROM); low birthweight, or preterm delivery before 37, 34, or 32 weeks. Risk factors for preterm delivery include being African-American, having a pelvic infection, and having a previous preterm delivery. Bacterial vaginosis is more common among African-American women, women of low socioeconomic status, and women who have previously delivered low birthweight infants.

Significant limitations to the findings include that studies comparing a screened population with a nonscreened population are absent. Also, results from the studies involving women at high risk for preterm delivery are varied and conflicting, which means insufficient evidence exists at this time to make a recommendation for or against screening in this population. Furthermore, methodological differences in the studies, as well as differing definitions of BV, made assimilating the data difficult.

US Preventive Services Task Force. Screening for bacterial vaginosis in pregnancy to prevent preterm delivery: US Preventive Services Task Force Recommendation Statement. Ann Intern Med. 2008;148:214-219.

Nygren P, Fu R, Freeman M, et al. Evidence on the benefits and harms of screening and treating pregnant women who are asymptomatic for bacterial vaginosis: an update review for the US Preventive Services Task Force. Ann Intern Med. 2008;148:220-233.