Treatment of bacterial vaginosis does not reduce preterm birth among high-risk asymptomatic women in fetal fibronectin positive patients.

Objective: Bacterial vaginosis (BV) is associated with preterm labor and may be positive in 15% of asymptomatic high-risk women. Fetal fibronectin (fFN) has been shown in symptomatic women to predict infection-related preterm birth. The purpose of this study was to quantitate the relationship between BV/fFN and preterm delivery in high-risk asymptomatic women.

Methods: Women at high-risk for spontaneous preterm delivery were tested for BV/fFN between 20-28 weeks gestation. Women positive for BV were treated with metronidazole, and fFN results were not used by physicians in treatment. After delivery, test results and pregnancy outcomes were entered in a deidentified database and analyzed.

Results: Of 232 women tested for BV/fFN over a 24-month epoch, results divided participants into 4 groups: Group A (N = 12; +BV/+fFN); Group B (N = 22; -BV/+fFN); Group C (N = 68; +BV/-fFN); and Group D (N = 130; -BV/-fFN). Demographics were the same between the 4 groups (P = NS) as was the gestational age at delivery (36.41 +/- 3.96 to 37.18 +/- 3.03 weeks). The incidence ofpreterm labor (P = .075), spontaneous early delivery (P = .936) and infants < 2500 gm (P = .664) was also similar.

Conclusions: In asymptomatic high-risk women, testing for fFN/BV during mid-pregnancy does not appear warranted.