Test Code FFN Fetal Fibronectin
Additional Codes
SHO4075
Performing Laboratory
Spectrum Laboratory
Available 24 hours, usual TAT 1 day.
Specimen Requirements and Processing
The Hologic Specimen Collection kit is the only acceptable specimen collection system that can be used to collect specimens for this assay.
Specimen Type: Vaginal Swab
Container/Tube: Hologic Specimen Collection
Kit (Rapid fFN)
Minimum volume: 250 µL
Collection Instructions: Follow directions in
collection kit for important detailed collection instructions and
restrictions.
1. During a speculum examination, prior to any examination or manipulation of the cervix or the vaginal tract, lightly rotate the sterile swab across the posterior fornix of the vagina for approximately 10 seconds to absorb cervicovaginal secretions. Subsequent attempts to saturate the swab may invalidate the test.
2. Remove swab and immerse tip in buffer. Break the shaft (at the score) even with the top of the tube.
3. Align the shaft with the hole inside the tube cap and push down tightly over the shaft, sealing the tube.
Warning: The shaft must be aligned to avoid leakage.
4. Write the patient’s name and other identifying information required on the specimen transport tube label.
5. Hand deliver the specimen to the laboratory.Transport specimens at 2 to 25°C, or frozen.
6. Specimens not tested within eight (8) hours of collection must be stored refrigerated at 2 to 8°C and assayed within three (3) days of collection, or frozen and assayed within three (3) months to avoid degradation of the analyte. Do not expose to temperatures above 25°C.
Special Instructions
Indication: 24 – 35 weeks gestation with suspicion of preterm labor. 22 – 30 weeks gestation with suspicion of high risk delivery.
Specimen not collected correctly will give inaccurate results. Unacceptable specimens: Bloody specimens. Collected in or by any sample device other than the Hologic Specimen Collection Kit. Insufficient volume. Unlabeled. Refrigerated specimens received greater than 3 days after the sampling date. Specimens received at temperatures greater than 25oC.
Reference Values
Reported as Negative (normal) or Positive (abnormal)
The test is performed using the Hologic Rapid fFN assay. The assay is designed for cervicovaginal secretions from symptomatic patients at gestational ages between 24 weeks 0 days and 34 weeks 6 days. A negative result indicates a <5% likelihood of delivery within 14 days. A positive result indicates an increased risk of delivery BUT NOT NECESSARILY imminent preterm delivery. A positive test warrants additional clinical decision making by obstetric staff based on patient presentation and history. Use of the test in asymptomatic patients has not yet been fully validated in the literature.
Specimen Stability
Ambient: 8 hours
Refrigerate: 72 hours
Frozen: 3 months (thaw only once)
Laboratory Retention: 48 hours
Methodology
Lateral flow, solid phase Immunochromatographic assay.
Specimen Transport Temperature
Refrigerate
Test Classification and CPT Coding
82731