The efficacy of quantitative fetal fibronectin in predicting spontaneous preterm birth in symptomatic women: A retrospective cohort study

Aust N Z J Obstet Gynaecol. 2019 Oct;59(5):656-661. doi: 10.1111/ajo.12947. Epub 2019 Feb 6.

Abstract

Background: Recent data suggest that quantitative measurements of fetal fibronectin can be used accurately to predict increased risk of preterm birth.

Aim: The purpose of this study was to demonstrate that the quantification of fetal fibronectin improves diagnostic accuracy in women who present with symptoms suggestive of threatened preterm labour (TPL) using a quantitative fetal fibronectin (qfFN) bedside analyser.

Study design: This was a retrospective cohort study of pregnant women who presented between 22+6 and 32+6 weeks gestation with symptoms of TPL who had qfFN measured using the Rapid fFN Q10 system. The ability to predict spontaneous preterm birth (sPTB) within 48 h, 14 days and <34 weeks gestation at qfFN thresholds of 10, 50 and 200 ng/mL was assessed.

Results: The overall rate of sPTB <34 weeks was 4.1% (n = 373). For deliveries within 48 h, within 14 days and <34 weeks, a qfFN threshold of 200 ng/mL had positive predictive values of 26.7%, 42.9% and 46.7%, respectively, when compared to patients with qfFN values of 0-9 ng/mL. The corresponding relative risks were 68.5, 53.8 and 38.0, respectively CONCLUSION: Quantitative fetal fibronectin testing with thresholds of 10, 50 and 200 ng/mL allows for more accurate prediction of preterm birth in symptomatic women. This higher degree of discrimination allows for more directed interventions for high-risk patients and reduces the cost and burden of unnecessary treatment for low-risk patients.

Keywords: fetal fibronectin; prediction; pregnancy; spontaneous preterm birth; symptomatic women.

MeSH terms

  • Adult
  • Cohort Studies
  • Female
  • Fetus / metabolism*
  • Fibronectins / blood*
  • Humans
  • Obstetric Labor, Premature / diagnosis
  • Predictive Value of Tests
  • Pregnancy
  • Premature Birth / diagnosis*
  • Prenatal Diagnosis*
  • Retrospective Studies

Substances

  • Fibronectins