Transvaginal Cervical Length (TVCL)

TVCL ≥ 30 mm (Low risk) (0 pts)+0TVCL 20–29 mm (Moderate risk) (+2 pts)+2TVCL 15–19 mm (High risk) (+4 pts)+4TVCL < 15 mm or cervical dilation ≥ 1 cm (Extreme high risk) (+6 pts)+6

Fetal Fibronectin (fFN) Test Result

fFN negative (< 50 ng/mL) (0 pts)+0fFN not performed or inconclusive (+1 pt)+1fFN positive (≥ 50 ng/mL) (+3 pts)+3

Prior Spontaneous Preterm Birth (< 37 Weeks)

No prior preterm birth (0 pts)+0Prior PTB at 34–36 weeks (+1 pt)+1Prior PTB at < 34 weeks (+2 pts)+2

Regular Uterine Contractions (≥ 4/20–30 min or ≥ 6/60 min)

No regular uterine contractions or irregular/mild (0 pts)+0Regular uterine contractions confirmed on toco (+2 pts)+2

Preterm Premature Rupture of Membranes (PPROM)

No PPROM — membranes intact (0 pts)+0PPROM confirmed (fluid pooling, + ferning, + nitrazine, Amnisure +) (+4 pts)+4

Preterm Labor Risk Assessment — fFN and Cervical Length

Preterm Labor Risk Assessment — fFN and Cervical Length