II. Indication

  1. Preterm Labor Evaluation

III. Mechanism

  1. Extracellular glycoprotein glues cell together
    1. Found between many cell types
    2. Binds placenta to Decidua
  2. Normally present in vagina in early pregnancy
    1. Not normally found in vagina after 20 weeks gestation
  3. Presense >20 weeks gestation suggests Preterm Labor

IV. Technique

  1. Do not obtain sample within 24 hours of vaginal exam
    1. Digital vaginal exam increases False Positive Rate

V. Interpretation

  1. Negative fibronectin is reassuring for 2 weeks
    1. If no cervical change, <10% preterm delivery risk
    2. Iams (2002) N Engl J Med 346:250-5 [PubMed]
  2. Positive fibronectin
    1. Once positive, no longer useful for monitoring
    2. Low Specificity for preterm delivery

VI. Efficacy

  1. Does not affect Gestational age at delivery
  2. Does not affect rate of inpatient admissions
  3. Does not affect frequency of medical interventions
  4. Lowe (2004) Am J Obstet Gynecol 190:358-62 [PubMed]

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Ontology: Fetal fibronectin (C0806123)

Concepts Biologically Active Substance (T123) , Amino Acid, Peptide, or Protein (T116)
SnomedCT 116666005
LNC LP19447-9, MTHU009189
English Fetal fibronectin, ffn, fetal fibronectin, Fibronectin.fetal, Fetal fibronectin (substance)
Spanish fibronectina fetal (sustancia), fibronectina fetal