title: Diagnostic value of cervical fetal fibronectin in detecting extrauterine pregnancy.
abstract: OBJECTIVE
  To determine whether fetal fibronectin (FFN) might serve as a marker to distinguish intrauterine versus extrauterine pregnancy.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Academic research center.
  
  
  METHODS
  Cervicovaginal FFN samples were obtained from 46 women who were at high risk for or presented with signs and/or symptoms of extrauterine pregnancy.
  
  
  METHODS
  Samples of blood were analyzed for FFN with use of an enzyme-linked immunoabsorbent assay (ELISA).
  
  
  METHODS
  Fetal fibronectin level.
  
  
  RESULTS
  The rate of extrauterine pregnancy in our study was 26.1%, with 12 extrauterine and 34 intrauterine pregnancies identified by ultrasonography or at time of surgery. Seventeen samples had FFN levels of > 50 ng/mL and were considered positive (range, 0-1,000 ng/mL). Positive FFN levels were observed in 41.7% (5 of 12) of women with extrauterine pregnancies versus 35.3%) (12 of 34) of women with intrauterine pregnancies. The sensitivity, specificity, and positive and negative predictive values for extrauterine pregnancy were 41.7%, 64.7%, 29.4%, and 75.9%, respectively.
  
  
  CONCLUSIONS
  The use of FFN does not appear to alter significantly the likelihood of identifying extrauterine pregnancy over current laboratory or ultrasonographic methods.
authors.affiliation: Department of Obstetrics and Gynecology, University of North Carolina at Chapel Hill 27599-7570, USA.
authors.forename: G E
authors.initials: GE
authors.lastname: Nowacek
authors.forename: W R
authors.initials: WR
authors.lastname: Meyer
authors.forename: M J
authors.initials: MJ
authors.lastname: McMahon
authors.forename: J R
authors.initials: JR
authors.lastname: Thorp
authors.forename: S R
authors.initials: SR
authors.lastname: Wells
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000032:analysis / Q000097:blood; D002584:Cervix Uteri / Q000737:chemistry*; D015331:Cohort Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005353:Fibronectins / Q000032:analysis* / Q000097:blood; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011271:Pregnancy, Ectopic / Q000175:diagnosis*; D011446:Prospective Studies; D012016:Reference Values; D012307:Risk Factors; D012680:Sensitivity and Specificity; D016216:Ultrasonography, Prenatal; D014626:Vaginal Smears
chemical_list: D015415:Biomarkers; D005353:Fibronectins