The Combination of the Fetal Fibronectin Bedside Test and Cervical Length in Preterm Labor Is Useful for Prediction of Preterm Birth

摘要

Objective: To determine the value of fetal fibronectin (FFN), cervical length (CL) measurement and their combination as binary predictors for preterm birth (PB) in women with preterm labour (PTL) between 24 + 0 and 34 + 0 weeks. Methods: One hundred fifty-nine patients with signs of PTL (singleton pregnancies (SP) = 125, twin pregnancies (TP) = 34) were evaluated in a retrospective study. Inclusion criteria were contractions > 4/20 min, intact membranes, no bleeding. The cut-off was ≥50 ng/ml for FFN and ≤20 mm for CL measured by transvaginal ultrasound. The primary outcome variable was delivery within 7 days from admission. Results: We evaluated 125 SPs and 34 TPs. In SPs, both methods had a sensitivity of 80%;the specificity was 82% for FFN, and 50% for CL. For the combination of both tests sensitivity was 80% and specificity 88%. In TPs, the sensitivity of both tests was lower (FFN 33%, CL 67%) but the combination of both tests represented the highest result for specificity (77% compared to 68% for FFN alone and 32% for CL alone). Conclusion: The combination of FFN and CL in PTL results in a significant higher specificity in SPs. In TPs the performance of the tests is less accurate.