Fetal fibronectin test

The fetal fibronectin test (fFN) is a test that can be perfomed on a vaginal swab to estimate the risk of preterm labour.


fFN is found at the interface of the chorion and the decidua (between the fetal sack and the uterine lining). It can be thought of as an adhesive or "biological glue" that binds the fetal sac to the uterine lining.

While a negative test is generally useful to rule out preterm labour (high negative predictive value), a positive test is not useful to predict the likelyhood (low positive predictive value).

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Article information

rID: 14747
System: Obstetrics
Tag: stub
Synonyms or Alternate Spellings:
  • Fetal fibronectin (ffn) test
  • Fetal fibronectin test (fFN)
  • fFN

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