title: Longitudinal changes in maternal soluble endoglin and angiopoietin-2 in women at risk for pre-eclampsia.
abstract: OBJECTIVE
  To investigate longitudinal changes in maternal plasma levels of soluble endoglin (sEng) and angiopoietin-2 (Ang-2) in pregnant women who develop pre-eclampsia (PE) and gestational hypertension (GH).
  
  
  METHODS
  This was a nested case-control study drawn from a larger prospective longitudinal study in singleton pregnancies identified by screening at 11 + 0 to 13 + 6 weeks' gestation as being at high-risk for PE. Blood samples were taken every 4 weeks until delivery. Values were compared in women who developed preterm PE (requiring delivery before 37 weeks), term PE, GH and those who remained normotensive.
  
  
  RESULTS
  A total of 471 samples were analyzed in 122 women, comprising 85 who remained normotensive, 12 who developed GH, 13 who developed term PE and 12 who developed preterm PE. In the normotensive group, there was an increase in log10 sEng levels with gestational age. In the preterm PE group, compared with the normotensive group, sEng was higher from 18 weeks onwards, and the difference increased significantly with gestational age (P < 0.001). In the GH and term PE groups, sEng did not differ significantly from that of the normotensive group (P = 0.583 and P = 0.890, respectively). The square root of Ang-2 decreased significantly with gestational age, but did not differ significantly among the different outcome groups (P = 0.571).
  
  
  CONCLUSIONS
  Maternal plasma sEng, but not Ang-2, may be a useful mid- and late-gestation biomarker for the development of PE.
authors.affiliation: Department of Fetal Medicine, St George's University of London, London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Khalil
authors.forename: N
authors.initials: N
authors.lastname: Maiz
authors.forename: R
authors.initials: R
authors.lastname: Garcia-Mandujano
authors.forename: M
authors.initials: M
authors.lastname: Elkhouli
authors.forename: K H
authors.initials: KH
authors.lastname: Nicolaides
mesh_terms: D000328:Adult; D042702:Angiopoietin-2 / Q000097:blood*; D015703:Antigens, CD / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure; D000071063:Endoglin; D005260:Female; D006801:Humans; D046110:Hypertension, Pregnancy-Induced / Q000097:blood; D008137:Longitudinal Studies; D011225:Pre-Eclampsia / Q000097:blood* / Q000175:diagnosis; D011247:Pregnancy; D011248:Pregnancy Complications / Q000378:metabolism; D011446:Prospective Studies; D011956:Receptors, Cell Surface / Q000097:blood*
chemical_list: D042702:Angiopoietin-2; D015703:Antigens, CD; D015415:Biomarkers; C064206:ENG protein, human; D000071063:Endoglin; D011956:Receptors, Cell Surface
keywords: angiopoietin-2; endoglin; gestational hypertension; pre-eclampsia; pregnancy screening