title: Mapping the theories of preeclampsia and the role of angiogenic factors: a systematic review.
abstract: OBJECTIVE
  To evaluate claims that elevated soluble fms-like tyrosine kinase-1 receptor (sFlt-1) and decreased placental growth factor predict preeclampsia.
  
  
  METHODS
  MEDLINE (1966-March 2006), EMBASE (1980-June 2006), POPLINE (1980-June 2006), CINAHL (1982-June 2006), and LILACS (1982-June 2006) were searched, and experts contacted.
  
  
  METHODS
  Studies identified and included were those reporting blood and urine levels of sFlt-1 or placental growth factor obtained before gestational week 30 or overt preeclampsia.
  
  
  RESULTS
  Ten of 184 available studies analyzing sFlt-1 and 14 of 319 studies analyzing placental growth factor were included in this review. There was considerable interreport heterogeneity in methodology and results for sFlt-1 measured before gestational week 25. After week 25 placental growth factor and sFlt-1 levels varied consistently between the normal pregnancy group and women destined to develop preeclampsia, achieving significance in women who developed severe preeclampsia.
  
  
  CONCLUSIONS
  Third-trimester increases in sFlt-1 and decreases in placental growth factor levels are associated with preeclampsia, specifically severe disease, based on retrospective data. The evidence is insufficient to recommend these markers to be used for screening, and prospective studies employing rigorous laboratory and study design criteria are needed to determine the clinical usefulness of these tests.
authors.affiliation: Nuffield Department of Obstetrics and Gynecology, University of Oxford, John Radcliffe Hospital, Oxford, UK.
authors.forename: Mariana
authors.initials: M
authors.lastname: Widmer
authors.forename: José
authors.initials: J
authors.lastname: Villar
authors.forename: Ariela
authors.initials: A
authors.lastname: Benigni
authors.forename: Agustin
authors.initials: A
authors.lastname: Conde-Agudelo
authors.forename: S Ananth
authors.initials: SA
authors.lastname: Karumanchi
authors.forename: Marshall
authors.initials: M
authors.lastname: Lindheimer
mesh_terms: D005260:Female; D006801:Humans; D000072483:Placenta Growth Factor; D011225:Pre-Eclampsia / Q000097:blood* / Q000209:etiology; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000097:blood*; D011263:Pregnancy Trimester, Third / Q000097:blood; D040281:Vascular Endothelial Growth Factor Receptor-1 / Q000097:blood*
chemical_list: C000608036:PGF protein, human; D011257:Pregnancy Proteins; D000072483:Placenta Growth Factor; D040281:Vascular Endothelial Growth Factor Receptor-1