First Trimester Maternal Screen
Method Description Describes how the test is performed and provides a method-specific reference
The first-trimester screen for trisomy 21 and trisomy 18 includes pregnancy-associated plasma protein A (PAPP-A), total human chorionic gonadotropin (ThCG), and nuchal translucency measurement. Analyte values are compared to median values at a given gestational age and multiple of the median (MoM) results obtained. The MoM results are used in a multivariate algorithm that includes the mother's age to derive risk factors for Down syndrome and trisomy 18. An interpretive report is provided. The Beckman Access ThCG assay is an automated 2-site, mouse monoclonal antibody-based immunoenzymatic sandwich assay with paramagnetic separation and chemiluminescent detection. Testing is performed using the Beckman Coulter DxI. (Beckman Coulter Assay Manual, Access Total HCG, 2010). The Access PAPP-A (RUO) assay is a two-site immunoenzymatic sandwich assay. Testing is performed using the Beckman Coulter DxI. (Package insert: Beckman Coulter Access PAPP-A [RUO[, Beckman Coulter, Inc., Fullerton CA 2009)
PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday; 5 a.m.-5 p.m.
Saturday; 6 a.m.-1 p.m.