title: Biomarkers and cervical length to predict spontaneous preterm birth in asymptomatic high-risk women.
abstract: OBJECTIVE
  To investigate whether biomarkers from different pathways of spontaneous preterm birth (cervical membrane degradation [fetal fibronectin], cervical remodeling [soluble E-cadherin], and inflammation (elafin, surfactant protein-D, interleukin-6 [IL-6]) were superior to one biomarker alone in predicting preterm birth. Our secondary objective was to examine the association of these biomarkers with cervical length in predicting preterm birth.
  
  
  METHODS
  We performed a single-center, prospective cohort study from August 2011 to November 2012 of asymptomatic women at risk for spontaneous preterm birth as a result of obstetric and gynecologic history. Cervicovaginal fluid and cervical length measurements were collected at two time points (20-23 6/7 weeks and 24-27 6/7 weeks of gestation).
  
  
  RESULTS
  Among the 104 women with complete data, the preterm birth rate was 24.5%. Prior preterm birth (P=.006) and cervical length at visit 1 (P=.003) were significantly associated with preterm birth, whereas fetal fibronectin and median biomarker levels (elafin, soluble E-cadherin, IL-6) were not. Median surfactant protein-D levels at visit 1 by preterm birth status were statistically but not clinically different (0.44 ng/mL compared with 0.40 ng/mL, P<.001). Analyses of biomarkers from more than one pathway were not superior to single biomarker analyses in predicting prematurity. Neither inclusion of biomarkers nor fetal fibronectin improved the predictive ability of cervical length alone.
  
  
  CONCLUSIONS
  Cervical length assessment and obstetric history but not fetal fibronectin or biomarkers were useful in the risk stratification of women identified to be at greatest risk for spontaneous preterm birth.
  
  
  METHODS
  II.
authors: Maternal and Child Health Research Program, Department of Obstetrics & Gynecology, Center for Research on Reproduction and Women's Health, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania.
authors: Jamie A
authors: JA
authors: Bastek
authors: Adi
authors: A
authors: Hirshberg
authors: Suchitra
authors: S
authors: Chandrasekaran
authors: Carter M
authors: CM
authors: Owen
authors: Laura M
authors: LM
authors: Heiser
authors: Brittany A
authors: BA
authors: Araujo
authors: Meghan A
authors: MA
authors: McShea
authors: Meghan E
authors: ME
authors: Ryan
authors: Michal A
authors: MA
authors: Elovitz
mesh_terms: D000328:Adult; D015415:Biomarkers; D054791:Cervical Length Measurement; D005260:Female; D006801:Humans; D011247:Pregnancy; D047928:Premature Birth; D011446:Prospective Studies; D018570:Risk Assessment
chemical_list: D015415:Biomarkers
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