title: Examining the relationship between positive mid-gestational fetal fibronectin assays and histological evidence of acute placental inflammation.
abstract: OBJECTIVE
  Both acute placental inflammation and positive mid-gestational cervico-vaginal fetal fibronectin assays have been independently correlated with preterm delivery. We conducted this study to examine the relationship between positive mid-gestational fetal fibronectin (fFN) assays and histological evidence of acute placental inflammation at delivery among women presenting with symptomatic preterm labor.
  
  
  METHODS
  This retrospective chart review included women who underwent cervico-vaginal fFN testing for preterm contractions between 24-34 weeks gestation and also had placental histological analysis after delivery. Women with a multiple gestation, cerclage, preterm premature rupture of membranes, intercourse or vaginal bleeding within 24 h before the assay were excluded. The primary outcome was histological evidence of acute placental inflammation defined as acute chorioamnionitis, acute deciduitis, funisitis, or microabscess formation.
  
  
  RESULTS
  Of 82 women who met all study inclusion criteria, 45% were fFN positive. Women with positive assays were no more likely to have histological evidence of acute inflammation noted at birth than women with negative assays (45% vs. 26%, P=0.07). The assay had a sensitivity of 58.6%, specificity of 62.3%, positive predictive value of 46.0%, and negative predictive value of 73.3% for predicting acute inflammation at delivery.
  
  
  CONCLUSIONS
  No association exists between positive fetal fibronectin assays and acute histologic placental inflammation at birth.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Magee-Womens Hospital, Pittsburgh, Pennsylvania 15213, USA. aakers@mail.magee.edu
authors.forename: Aletha
authors.initials: A
authors.lastname: Akers
authors.forename: Jason A
authors.initials: JA
authors.lastname: Jarzembowski
authors.forename: Clark T
authors.initials: CT
authors.lastname: Johnson
authors.forename: Richard W
authors.initials: RW
authors.lastname: Lieberman
authors.forename: Vanessa K
authors.initials: VK
authors.lastname: Dalton
mesh_terms: D000328:Adult; D002821:Chorioamnionitis / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005353:Fibronectins / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D007752:Obstetric Labor, Premature / Q000378:metabolism*; D010920:Placenta / Q000473:pathology*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second / Q000378:metabolism; D011263:Pregnancy Trimester, Third / Q000378:metabolism; D012189:Retrospective Studies
chemical_list: C403421:FFN protein, human; D005353:Fibronectins; D006023:Glycoproteins