title: Evaluation of a quantitative fetal fibronectin test for spontaneous preterm birth in symptomatic women.
abstract: OBJECTIVE
  The purpose of this study was to determine whether quantification of cervicovaginal fluid fetal fibronectin (fFN) improves diagnostic accuracy of spontaneous preterm birth (sPTB) in symptomatic women.
  
  
  METHODS
  A prospective blinded predefined secondary analysis of a larger study of cervicovaginal fluid fFN concentration (nanograms per milliliter) in women symptomatic of preterm labor (n =300 women; 22-35 weeks' gestation) with a Hologic 10Q system (Hologic, Marlborough, MA). Clinicians were blinded to the result until after the delivery, but the qualitative Hologic TLI(IQ) fFN result was made available.
  
  
  RESULTS
  The positive predictive value for sPTB (<34 weeks' gestation) increased from 19%, 32%, 61%, and 75% with increasing thresholds (10, 50, 200, and 500 ng/mL, respectively). Compared with <10 ng/mL fFN, the relative risk of delivery was 5.6 (95% confidence interval [CI], 1.05-29.57), 7.9 (95% CI, 1.38-45.0), 22.8 (95% CI, 3.84-135.5), and 51.3 (95% CI, 12.49-211.2; P < .01).
  
  
  CONCLUSIONS
  Quantitative fFN provides thresholds (10 and 200 ng/mL) in addition to the qualitative method (50 ng/mL) to discriminate the risk of sPTB in symptomatic women.
authors.affiliation: Division of Women's Health, King's College London, Women's Health Academic Centre, Kings Health Partners, St. Thomas' Hospital, London, England, UK.
authors.forename: Danielle S
authors.initials: DS
authors.lastname: Abbott
authors.forename: Samara K
authors.initials: SK
authors.lastname: Radford
authors.forename: Paul T
authors.initials: PT
authors.lastname: Seed
authors.forename: Rachel M
authors.initials: RM
authors.lastname: Tribe
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Shennan
mesh_terms: D000328:Adult; D002584:Cervix Uteri / Q000378:metabolism*; D005260:Female; D005353:Fibronectins / Q000378:metabolism*; D005865:Gestational Age; D006801:Humans; D011237:Predictive Value of Tests; D011247:Pregnancy; D047928:Premature Birth / Q000175:diagnosis*; D011296:Prenatal Diagnosis / Q000379:methods*; D011446:Prospective Studies; D014626:Vaginal Smears; D055815:Young Adult
chemical_list: D005353:Fibronectins