title: Human placental lactogen is a first-trimester maternal serum marker of Down syndrome.
abstract: BACKGROUND
  Human placental lactogen (hPL) is synthesised by the placenta and found in maternal serum. We analysed the potential of hPL as a first-trimester maternal serum-screening marker for fetal Down syndrome (DS).
  
  
  METHODS
  hPL was quantified by ELISA in 47 DS pregnancies and 136 controls in gestational weeks 8-13. Distributions of log multiples of the median (MoMs) were established. The quantity of hPL in DS screening was estimated using Monte Carlo simulation methods.
  
  
  RESULTS
  The mean log10 MoM hPL was - 0.1995 (SD: 0.1993) in affected and 0.0026 (SD: 0.2129) in control pregnancies. This corresponds to a MoM of 0.63 in DS pregnancies. hPL correlated significantly with log10 MoM values of hCGbeta (r = 0.320) and PAPP-A (r = 0.590) in controls, but not with hCGbeta (r = 0.228) or PAPP-A (r = 0.090) in DS pregnancies. The inclusion of hPL in the double test (PAPP-A + hCGbeta) increased the detection rate from 67 to 75% for a false-positive rate of 5%.
  
  
  CONCLUSIONS
  hPL is a DS screening marker that is applicable at weeks 9-13 and could be included in multiple marker first-trimester screening for DS.
authors.affiliation: Department of Clinical Biochemistry, Statens Serum Institut, Copenhagen, Denmark. mic@ssi.dk
authors.forename: Michael
authors.initials: M
authors.lastname: Christiansen
authors.forename: Tina Lindvig
authors.initials: TL
authors.lastname: Sørensen
authors.forename: Bent
authors.initials: B
authors.lastname: Nørgaard-Pedersen
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood*; D000078842:Cytoglobin; D004314:Down Syndrome / Q000097:blood* / Q000175:diagnosis*; D005260:Female; D005914:Globins / Q000032:analysis; D006801:Humans; D008875:Middle Aged; D010928:Placental Lactogen / Q000097:blood*; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000097:blood*; D011266:Pregnancy-Associated Plasma Protein-A / Q000032:analysis; D011296:Prenatal Diagnosis
chemical_list: D015415:Biomarkers; D000078842:Cytoglobin; D005914:Globins; D010928:Placental Lactogen; D011266:Pregnancy-Associated Plasma Protein-A