Predictive value of the Quantitative fetal fibronectin levels for the management of women presenting with threatened preterm labour – A revised cut off level: A retrospective cohort study

Abstract Objective To evaluate a new a cut off level of fetal fibronectin as a predictor of birth in women with threatened preterm labour. Design A retrospective cohort study performed at Ipswich hospital, Ipswich, Queensland, Australia, in women with threatened preterm labour with intact membranes between 23 weeks to 34 + 6 week gestation. Study Design A quantitative fetal fibronectin (fFN) was performed. Maternal demographics and birth outcome data were extracted from the routinely collected perinatal data held by the hospital. The odds of preterm birth were estimated for each cut off value of fFN (10, 50 and 200 ng/ml) using logistic regression and accounting for multiple presentations by the same woman. Results Among the 447 presentations and 376 pregnancies, rates of preterm birth Conclusion In women presenting with TPL, those with levels of