Does midtrimester Nugent score or high vaginal pH predict gestational age at delivery in women at risk for recurrent preterm birth?

Abstract

To estimate whether bacterial vaginosis, as defined by either Nugent score or vaginal pH, predicts gestational age at delivery in women at risk for recurrent preterm birth. Planned secondary analysis of a randomized cerclage trial in women with prior spontaneous preterm birth 17⁰(/)⁷-33⁶(/)⁷ weeks. Vaginal Gram stain and pH were collected at the initial study visit. Women not assigned to cerclage, either because they did not experience cervical shortening <25 mm or because they were randomly assigned to no cerclage, were studied. Seven hundred eighty-six women had complete delivery gestational age, Gram stain, and pH results. The diagnosis of bacterial vaginosis by either Nugent score ≥ 7 or by pH ≥ 5 was not associated with earlier birth. The presence of bacterial vaginosis at 16-21⁶(/)⁷ weeks does not predict gestational age at birth in women at risk for recurrent preterm birth.