Table 5.

Test characteristics of fetal fibronectin for predicting spontaneous preterm birth in singletons.

	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)
CL ≤ 10 mm (n = 40)
Delivery < 7 days	100	64.9	18.6	100
Delivery < 14 days	100	66.7	25	100
Delivery < 34 weeks	80	73.9	57.1	89.5
Delivery < 37 weeks	58.8	73.9	62.5	70.8
CL 11–25 mm (n = 77)
Delivery < 7 days	100	78	5.8	100
Delivery < 14 days	100	73.2	11.8	100
Delivery < 34 weeks	58.3	84.7	50	88.6
Delivery < 37 weeks	35.7	84.7	58.8	68.4

CL, cervical length; PPV, positive predictive value; NPV, negative predictive value