Professional Resources

FAQs, publications and additional resources regarding the Rapid fFN® test.

Frequently asked questions

What is fetal fibronectin testing?

Fetal fibronectin (fFN) is a “glue-like” protein that helps bond the baby to the uterus. Fetal fibronectin is detectable in vaginal secretions in the very beginning of pregnancy, when this bond is first forming and then again at the end of pregnancy, when your body is getting ready to deliver your baby. If fetal fibronectin is detectable in vaginal discharge between 22 and 35 weeks, this could indicate the “glue” is leaking prematurely and preterm delivery is a real possibility.

Where is the Rapid fFN® test used?

In over 2,000 birthing hospitals across the United States.1

Which patients can receive a Rapid fFN® test?

Patients presenting with signs or symptoms of preterm labor are eligible to receive a Rapid fFN® test.2
These may include:3

  • Contractions every 10 minutes or more often
  • Change in vaginal discharge (leaking fluid or bleeding from the vagina)
  • Pelvic pressure (the feeling that your baby is pushing downward)
  • Abdominal cramps with or without diarrhea
  • Low, dull backache

The Rapid fFN® test can be used on both symptomatic singleton and twin pregnancies.2

When can the test be performed?

fFN testing is FDA approved in symptomatic patients between 24 and 346 weeks gestation.2 The FDA has also approved fFN testing for asymptomatic patients at risk of preterm delivery between 22 and 306 weeks gestation.2

Why is the test performed?

To determine a woman’s risk of preterm delivery in the next 7-14 days.2 Results can be useful when trying to determine whether to admit her to the hospital and when to administer antenatal corticosteroids.

How is the specimen collected? 4

  • The specimen must be collected prior to other vaginal exams, without gels or lubricants.
  • During speculum exam, lightly rotate swab across posterior fornix of vagina for 10 seconds to absorb cervicovaginal secretions.
  • Remove swab and immerse polyester tip in buffer; break shaft at score even with top of tube.
  • Align the shaft with hole inside the tube cap and push down tightly over shaft, sealing tube; ensure shaft is aligned

What are contraindications for collecting/sending a specimen for an fFN test?

  • Dilation > 3 cm
  • Moderate or gross vaginal bleeding (spotting is OK)
  • Placental abruption or placenta previa
  • Rupture of membranes

If none of the above contraindications are present, it is appropriate to send the fFN sample to the lab according to instructions for use. 2,4

Can I collect a specimen if the patient has had sex in the last 24 hours?

Yes. A negative fFN result is valid even if she’s had sex in the last 24 hours. Semen will not cause a false negative, bit it can occasionally cause a false positive. So a positive result, in this situation, may not be valid and should be confirmed after 24 hours.4

How are fFN results interpreted?

  • The Rapid fFN® test has an FDA-approved negative predictive value (NPV) of 99.2%, meaning that the patient has <1% chance of delivery with a negative result in the next 14 days.2
  • The Rapid fFN® test also has the best sensitivity available (86%) for ruling out preterm labor and is the only FDA-approved test to assess the risk of preterm delivery that has both a t and 14-day indication. 2,5

How many patients will receive a negative result?

The vast majority of patients, ~80%, will receive a negative result allowing you to focus on the 20% that really are at the highest risk.2

How long does it take to run the test?

  • Once the collected specimen arrives in the lab, it takes < 30 minutes for the TLiIQ analyzer to produce an fFN test result.2
  • The lab can likely provide a test result within 1 hour if the fFN sample is sent immediately (check with your
    internal process).

How long is the specimen viable?

  • The specimen can be stored at room temperature for up to 8 hours before testing or kept refrigerated for up to 3 days before testing.4
  • While an fFN sample is typically collected in L&D when a patient presents with symptoms of preterm labor, this lengthy period of viability also give providers the flexibility to collect the fFN sample in the office prior to conducting a digital exam and then sending it with the patient to L&D.

What does an fFN test cost?

  • The cost of the Rapid fFN® test itself is covered by many insurance policies; however, costs to patients will vary depending on their individual insurance.
  • Specimen collection swabs are FREE and can be ordered by calling Hologic customer support at 1-800-442-9892 or by emailing
  • Remember to always collect an fFN specimen from each patient who presents with symptoms of preterm prior to doing a digital exam. The, if the specimen cannot be sent to the lab due to a contraindication identified later during the exam, there is NO CHARGE since the fFN collection swabs are free.


General fFN Studies

2017, Ruma
Current Perspectives on the Use of Fetal Fibronectin Testing in Preterm Labor Diagnosis and Management
2017, McCue
Fetal Fibronectin: The Benefits of a High Negative Predictive Value in Management of Preterm Labor
2017, Blackwell
Utilization of Fetal Fibronectin Testing and Pregnancy Outcomes Among Women with Symptoms of Preterm Labor
2001, Lockwood
Risk Stratification and Pathological Mechanisms in Preterm Delivery
2000, Goldenberg
The Preterm Prediction Study: Sequential Cervical Length and Fetal Fibronectin Testing for the Prediction of Spontaneous Preterm Birth
1997, Peaceman
Fetal Fibronectin as a Predictor of Preterm Birth in Patients with Symptoms: A Multicenter Trial


2018, Chiossi
Using Cervical Length Measurement for Lower Spontaneous Preterm Birth Rates Among Women with Threatened Preterm Labor
2017, Boelig
Assessment of Transvaginal Ultrasound Cervical Length Image Quality
2016, Chory
ACES: Accurate Cervical Evaluation with Sonography
2015, Hermans
Risk Stratification with Cervical Length and Fetal Fibronectin in Women with Threatened Preterm Labor before 34 Weeks and Not Delivering within 7 Days
2014, Parry
Pros and Cons of Maternal Cervical Length Screening to Identify Women at Risk of Spontaneous Preterm Delivery
2013, Van Baaren
Cost-Effectiveness Analysis of Cervical Length Measurement and Fibronectin Testing in Women with Threatened Preterm Labor
2013, Iams
Adherence to Criteria for Transvaginal Ultrasound Imaging and Measurement of Cervical Length
2013, DeFranco
Improving the Screening Accuracy for Preterm Labor: Is the Combination of Fetal Fibronectin and Cervical Length in Symptomatic Patients a Useful Predictor of Preterm Birth? A Systematic Review
2008, Schmitz
Selective Use of Sonographic Cervical Length Measurement for Predicting Imminent Preterm Delivery in Women with Preterm Labor and Intact Membranes
2005, Gomez
Cervicovaginal Fibronectin Improves the Prediction of Preterm Delivery Based on Sonographic Cervical Length in Patients with Preterm Uterine Contractions and Intact Membranes
2000, Goldenberg
The Preterm Prediction Study: Sequential Cervical Length and Fetal Fibronectin Testing for the Prediction of Spontaneous Preterm Birth

Clinical Assessment

2009 How
Cervical dilatation on presentation for preterm labor and subsequent preterm birth.
1998, Goldenberg
The Preterm Prediction Study: The Value of New vs. Standard Risk Factors in Predicting Early and All Spontaneous Preterm Births
1995, Phelps
Accuracy and Intraobserver Variability of Simulated Cervical Dilatation Measurements
1994, Iams
Fetal Fibronectin Improves the Accuracy of Diagnosis of Preterm Labor

Standardization & cost savings

2013, Van Baaren
Cost-Effectiveness Analysis of Cervical Length Measurement and Fibronectin Testing in Women with Threatened Preterm Labor
2013, Lucovnik
Cost of Unnecessary Admissions and Treatments for “Threatened PTL”
2013, Iyer
The association of fFN testing on hospital admissions for preterm labor
2010, Rose
Cost-Effective Standardization of Preterm Labor Evaluation
2010, Dutta
The Efficacy of Fetal Fibronectin Testing in Minimising Hospital Admissions, Length of Hospital Stay and Cost Savings in Women Presenting with Symptoms of Pre-Term Labour
2006, Ness
Impact of the Recent Randomized Trials on the Use of Progesterone to Prevent Preterm Birth: A 2005 Follow-Up Survey
2000, Giles
The Effect of Fetal Fibronectin Testing on Admissions to a Tertiary Maternal Fetal Medicine Unit and Cost Savings
1999, Joffe
Impact of Fetal Fibronectin Assay on Admissions for Preterm Labor

Antenatal steroids

2015, Wilms
Prescribing Patterns of Antenatal Corticosteroids in Women with Threatened Preterm Labor
2015, Razaz
Trends in Optimal, Suboptimal, Questionably Appropriate Receipt of Antenatal Corticosteroid Prophylaxis
2011, Wilms
Relationship Between the Time Interval from Antenatal Corticosteroid Administration Until Preterm Birth and the Occurrence of Respiratory Morbidity
2000, Honest
Accuracy of Cervicovaginal Fetal Fibronectin Test in Predicting Risk of Spontaneous Preterm Birth: Systematic Review


2018, Fuchs
Accuracy of Fetal Fibronectin for the Prediction of Preterm Birth in Symptomatic Twin Pregnancies: A Pilot Study
2007, Singer
Accuracy of Fetal Fibronectin to Predict Preterm Birth in Twin Gestations with Symptoms of Labor

Package inserts and IFUs

For package insert information, IFUs and user guides click the link below.

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