Rapid fetal fibronectin testing to predict preterm birth in women with symptoms of premature labour: a systematic review and cost analysis.

Premature birth is defined as birth of before 37 completed weeks' gestation. Not all pregnant women showing symptoms of preterm labour will go on to deliver before 37 weeks' gestation. Hence, addition of fetal fibronectin (fFN) testing to the diagnostic workup of women with suspected preterm labour may help to identify those women who do not require active management, and thus avoid unnecessary interventions, hospitalisations and associated costs.