Fetal Fibronectin

Specimen Type: Swab

Collection Container/Type: Hologic fFN Collection Kit

Specimen Volume: Swab

Collection Instructions: 

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 the Hologic Perinatal Swab (sterile, polyester-tipped 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. Send the tube to the laboratory for testing. Transport specimens at 2° to 25°C, or frozen.


5. 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.

Room temperature: Unacceptable

Refrigerated: 3 days

Frozen: 3 months

• Specimens collected in or by any sample device other than the Hologic Specimen Collection Kit.
• Specimens with insufficient volume for testing.
• Specimens received unlabeled.
• Specimens received > 3 days after the sampling date at 2° to 8°C.
• Specimens received at temperatures >25°C.
• Frozen specimens received > 3 months after sampling date

Same day

• The Rapid fFN result should not be interpreted as absolute evidence for the presence or absence of a process that will result in delivery in less than or equal to 7 or 14 days from specimen collection in symptomatic women or delivery in less than or equal to 34 weeks, 6 days in asymptomatic women evaluated between 22 weeks, 0 days and 30 weeks, 6 days of gestation. A positive fFN result may be observed for patients who have experienced cervical disruption caused by, but not limited to, events such as sexual intercourse, digital cervical examination, or vaginal probe ultrasound. The Rapid fFN result should always be used in conjunction with information available from the clinical evaluation of the patient and other diagnostic procedures such as cervical examination, cervical microbiological culture, assessment of uterine activity, and evaluation of other risk factors.
• Modification of the assay protocol described herein may yield erroneous results.
• The assay has been optimized with specimens taken from the posterior fornix of the vagina or the ectocervical region of the external cervical os. Samples obtained from other locations should not be used.
• The safety and effectiveness of using a cutoff other than that provided by the Rapid fFN Cassette Calibration Code has not been established.
• Assay interference from the following components has not been ruled out: douches, white blood cells, red blood cells, bacteria and bilirubin.
• The presence of infections has not been ruled out as a confounding factor to risk of preterm delivery.
• Assay interference from semen has not been ruled out. Specimens should not be collected less than 24 hours after intercourse. However, even when a patient reports having had intercourse in the previous 24 hours, a negative fetal fibronectin test result is valid.
• Manipulation of the cervix may lead to false positive results. Specimens should be obtained prior to digital examination or manipulation of the cervix.
• Care must be taken not to contaminate the swab or cervicovaginal secretions with lubricants, soaps, disinfectants, or creams (e.g., K-Y® Jelly lubricant, Betadine® disinfectant, Monistat® cream, hexachlorophene). These substances may interfere with absorption of the specimen by the swab
• or with the antibody-antigen reaction of the Rapid fFN test.
• Patients with suspected or known placental abruption, placenta previa, or moderate or gross vaginal bleeding should not be tested for fFN