Why test for fFN?

Determining who is really at risk for preterm birth can be a major challenge. Fetal fibronectin (fFN) testing can help rule out 80% of patients presenting with symptoms of preterm labor.1

Qual Glue Upside Down Baby 30week

Fetal fibronectin is an adhesive glycoprotein “glue” at the maternal-fetal interface and is a common biomarker for all 4 mechanisms of preterm birth.1,2 It is indicated for singleton and twin pregnancies.1

Gestational window for the fetal fibronectin test

  • Women with symptoms of PTL from 240 – 346 weeks gestation
  • Asymptomatic women from 220 – 306 weeks gestation

Negative Test Icon 1

fFN test advantages1

  • Result is objective, not subjective
  • Reliably high NPV for both ≤ 7 and 14 days
  • ~80% of patients will receive a negative result
  • Can be used on both singleton and twin pregnancies
  • Results <30 minutes after test initiation
  • Sample can be collected for FREE
  • Sample is valid for up to 8 hours at room temperature or 3 days refrigerated
  • A negative result is valid even if a patient has had sex in the previous 24 hours
  • The Rapid fFN® test has the best sensitivity for ruling out preterm labor1,3

Improved sPTB prediction with cervical length + fFN


Using fFN testing, in addition to measuring cervical length with transvaginal ultrasound (TVUS), increases the predictivity of cervical length results by as much as 50%.4

Risk of sPTB in patients with symptoms of preterm labor:
Improved sPTB Prediction Infographic

fFN testing can help optimize resources


Standardizing preterm labor evaluations reduces unnecessary admissions and interventions.5 Data shows that adding fFN to PTL triage reduces length of stay. In one study, adding fFN testing reduced the average hospital stay from 5.2 days to 0.6 days.6

Adding fFN testing dramatically reduced unnecessary admissions
ffn testing case study 1

Case Study 1: Brigham and Women’s Hospital

At the Brigham and Women’s Hospital the introduction of fFN in PTL triage led to a decrease in unnecessary admissions.7

ffn testing case-study

Case Study 2: Mayo Clinic

The Mayo Clinic reduced the rate of hospital admissions by 56% and reduced the average length of stay by 4.5 days.6


International fFN testing


Outside of the United States there are two types of fFN tests available.

Quantitative fFN Testing

The Quantitative fFN test provides a patient’s quantitative level of fFN on a scale of 0 ng/mL to 500 ng/mL, unlike the U.S. Rapid fFN® test which provides a positive or negative result based on a 50 ng/mL cut-off.

Visit the U.K. fFN website for more information.

QuikCheck™ fFN Testing

The QuikCheck fFN test is an alternative visual-read fFN test for non-U.S. hospitals in triage locations where using the Rapid fFN® analyzer-read test is not possible.


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Contact us for more information about the Rapid fFN® test.