Laboratory Lab results are too important to go anywhere else.

Fetal Fibronectin

FFN

Test Codes

EPIC: LAB5048, FFN

Department

Chemistry

Instructions

Only Hologic swabs transported in an appropriate buffer will be accepted for this test. Supplies can be obtained from:

• Farmington Hills: New Beginnings Maternity Center, 248-471-8000 
• Grosse Pointe: Chemistry Laboratory, 313-473-1807
• Royal Oak: Family Birthing Center Triage, 248-898-5574
• Troy: Obstetrics Triage, 248-964-5000
• Outreach: Local Hologic® Representative, 800-442-9892

Specimen Collection Criteria

Collect: Hologic® swab in appropriate buffer.

• Obtain using speculum examination without lubricant, before the manual exam.
• Lightly rotate swab across the posterior vaginal fornix for 10 seconds to absorb vaginal secretions.

Physician Office/Draw Specimen Preparation

Specimens should not be exposed to temperatures greater than 25°C (77°F). Maintain specimens refrigerated (2–8°C or 36–46°F) and transport to the Laboratory within 8 hours of collection.

Preparation for Courier Transport

Transport: Hologic® swab in appropriate buffer, refrigerated (2–8°C or 36–46°F).

Rejection Criteria

Specimens not collected with the Hologic® swab in appropriate buffer.

Inpatient Specimen Preparation

Transport specimens immediately after collection to the STAT Laboratory (Royal Oak) or Chemistry Laboratory (Dearborn, Farmington Hills, Grosse Pointe and Troy).

Storage

Specimen Stability for Testing:

Room Temperature (20–26°C or 68–78.8°F): 8 hours
Refrigerated (2–8°C or 36–46°F): 72 hours
Frozen (-20°C/-4°F or below): 3 months

Specimen Storage in Department Prior to Disposal:

Refrigerated (2–8°C or 36–46°F): 7 days

Laboratory

Dearborn Chemistry Laboratory
Farmington Hills  Chemistry Laboratory
Grosse Pointe  Chemistry Laboratory
Royal Oak STAT Laboratory
Troy Chemistry Laboratory

Performed

Sunday – Saturday, 24 hours a day.
STAT results available within 60 minutes of receipt in the Laboratory.
Routine results available within 4 hours of receipt in the Laboratory.

Reference Range

Negative (Less than 50 ng/mL).

Test Methodology

Qualitative Immunoassay.

Interpretation

The test is a rapid assay designed for the evaluation of threatened preterm labor. Fetal fibronectin (fFN) is a normal constituent of the pregnant uterus and is found in the vagina before 20 weeks gestation. Studies have shown that, if vaginal fluid is negative for fetal fibronectin in a symptomatic patient with preterm labor (between 24 and 34 weeks gestation), the risk of spontaneous preterm birth in the next 7 – 14 days is 0 – 4%.

Clinical Utility

All the criteria listed below must be met for a valid result:

• Signs/symptoms of preterm labor with uterine contractions at least every 8-10 minutes
• Gestational age 24 0/7 - 34 6/7 weeks
• Intact amniotic membranes
• Abnormal cervical exam (dilation or effacement) or cervical change from previous documented examination
• Cervix dilated less than 3 cm.

Testing should not be performed if there is vaginal bleeding or if there has been a cervical exam, transvaginal ultrasound or sexual intercourse in the previous 24 hours.

CPT Codes

82731
LOINC: 20404-0

Contacts

Last Updated

2/20/2023