title: [Focus on preanalytics for Down's syndrome screening during first trimester of pregnancy].
abstract: The aim of the study is to specify the pre-analytical conditions required for Down's syndrome screening in first trimester by maternal serum markers. The concentration variation of both markers, hCGβ and PAPP-A, was analyzed at room temperature, at 4°C and during freezing-thawing cycles. Serum can be kept during 72h between 2 and 8°C with an acceptable bias of 5% for each marker. It can also undergo three freezing-thawing cycles without any variation of results. Preservation at room temperature (between 20 and 25°C) requires an analysis within 24h. From this study, writing recommendations enable to give a precise frame to pre-analytical processing and transport of blood samples, in a field where variations can lead to heavy therapeutic decisions.
authors.affiliation: Service d'hématologie et microbiologie, Laboratoire de biologie médicale, Centre hospitalier de Chambéry, France.
authors.forename: Rémi
authors.initials: R
authors.lastname: Gebeile
authors.affiliation: Service de biochimie, Laboratoire de biologie médicale, Centre hospitalier de Chambéry, France.
authors.forename: Christelle
authors.initials: C
authors.lastname: Roger
authors.affiliation: Service de biochimie, Laboratoire de biologie médicale, Centre hospitalier de Chambéry, France, ProBioQual, Lyon, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Doche
authors.affiliation: ProBioQual, Lyon, France, LBM MS LabosChambéry, La Motte Servolex, France.
authors.forename: Laurence
authors.initials: L
authors.lastname: Doche
mesh_terms: D015415:Biomarkers / Q000097:blood; D001793:Blood Preservation / Q000379:methods*; D001800:Blood Specimen Collection / Q000379:methods*; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D004314:Down Syndrome / Q000097:blood / Q000175:diagnosis*; D005260:Female; D006801:Humans; D011237:Predictive Value of Tests; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000097:blood*; D011266:Pregnancy-Associated Plasma Protein-A / Q000032:analysis*; D011296:Prenatal Diagnosis / Q000379:methods*; D013696:Temperature
chemical_list: D015415:Biomarkers; D018997:Chorionic Gonadotropin, beta Subunit, Human; D011266:Pregnancy-Associated Plasma Protein-A
keywords: Down's syndrome; PAPP-A; free beta hCG; preanalytics