title: First trimester PAPP-A2, PAPP-A and hCGβ in small-for-gestational-age pregnancies.
abstract: BACKGROUND
  Pregnancy-associated plasma protein-A2 (PAPP-A2) is a recently discovered protease that cleaves a subset of insulin-like growth factor binding proteins (IGFBP). The molecular function suggests its involvement in the IGF system that is vital for fetal growth and development. Our objectives were to establish first trimester median curves of PAPP-A2, PAPP-A and hCGβ for singleton normal pregnancies and to investigate whether an altered level of one or more of the biomarkers is associated with small-for-gestational-age (SGA) neonates before and after stratification according to maternal hypertension and/or proteinuria.
  
  
  METHODS
  This was a case-control study based on 985 pregnant women delivering normal-weighted neonates and 170 pregnant women delivering SGA neonates. PAPP-A2 was measured by ELISA. PAPP-A and hCGβ were measured by an automatic analyzer. Median curves from 8+1 to 14+0 were established and all concentration values were converted to multiples of the median (MoM) values.
  
  
  RESULTS
  Before stratification the SGA cases had unaffected PAPP-A2 MoM and hCGβ MoM levels but lower PAPP-A MoM compared with normal controls. After stratification the SGA normotensive subgroup had lower PAPP-A2 MoM and PAPP-A MoM levels than the normal normotensive subgroup. Severe preeclamptic women delivering SGA neonates had higher PAPP-A2 MoM compared to the normotensive women delivering SGA neonates.
  
  
  CONCLUSIONS
  Pregnant women delivering SGA neonates did not have altered levels of PAPP-A2 or hCGβ but had lower PAPP-A level in the first trimester compared with pregnant women delivering normal-weighted neonates. Pregnancies complicated with severe preeclampsia and SGA may be associated with high PAPP-A2 level.
authors.forename: Young Bae
authors.identifier: http://orcid.org/0000-0002-8428-560X
authors.initials: YB
authors.lastname: Hansen
authors.forename: Vibeke
authors.initials: V
authors.lastname: Myrhøj
authors.forename: Finn Stener
authors.initials: FS
authors.lastname: Jørgensen
authors.forename: Claus
authors.initials: C
authors.lastname: Oxvig
authors.forename: Steen
authors.initials: S
authors.lastname: Sørensen
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D005260:Female; D005317:Fetal Growth Retardation / Q000097:blood*; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000097:blood*; D011266:Pregnancy-Associated Plasma Protein-A / Q000032:analysis*
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human; C430889:PAPPA2 protein, human; D011266:Pregnancy-Associated Plasma Protein-A; C579283:PAPPA protein, human