FFN - Hologic Rapid fFN


The fFN test is FDA-approved for use as an aid in assessing the risk of preterm delivery in two patient populations: 1) symptomatic women from 24-35 weeks gestation and 2) asymptomatic women from 22-31 weeks gestation. The fFN test should NOT be used for symptomatic women with one or more of the following conditions: 1) advanced cervical dilation (≥3 cm), 2) rupture of amniotic membranes, 3) cervical cerclage, or 4) moderate or gross vaginal bleeding. The fFN test should NOT be used for asymptomatic women with one or more of the following conditions: 1) multiple gestations, 2) cervical cerclage, 3) placenta previa, or 4) sexual intercourse in the preceding 24 hours (fFN has been detected in sperm).

Specimen Collection Requirements


Cervicovaginal secretions, one Hologic Rapid fFN collection kit.


Specimens must be collected according to the FDA approved protocol using the Hologic Rapid fFN Specimen Collection Kit. The specimen is collected from the posterior fornix of the cervical os. Place the specimen in the transfer tube buffer and cap securely. Place the specimen in wet ice or refrigerate (2-8°C) and transport the specimen to the laboratory. Refer to the detailed specimen collection procedure available from the laboratory for precise instructions.

Preferred Volume

0.50 mL (one collection tube)

Minimum Volume

0.25 mL


Refrigerated (2-8°C)

Rejection Criteria

Specimens collected in or by any sample device other than the Hologic Rapid fFN Specimen Collection Kit.

Grossly bloody samples.


Ambient (15-25°C): 8 hours; Refrigerated (2-8°C): 3 days; Frozen (at or below -20°C): 3 months

Testing Information


7 days/week



Referral Lab

Samaritan Health Services Laboratories

Reference Values

Reference Values

Risk of Preterm Delivery Given a Negative or Positive Result1

Test Result Symptomatic Women Asymptomatic Women
  Risk of delivery in = 14 days from collection of specimen: Risk of delivery before 35 weeks gestation:
Negative 0.8% 3.8%
Positive 16.7% 31.7%



CPT Codes


Last Updated: Thursday, January 5, 2017 03:42:10 AM