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What is Screening test used in first trimester for aneuploidy - and explain in detail?
Ans. is'c'i.e., PAPP-A &beta HCG1st trimester aneuploidy screening:Human chorionic gonadotropin (either intact or free (b-hCG).Pregnancy-associated plasma protein A (PAPP-A).Fetal Down syndrome in 1st trimester:Higher serum free beta-hCG level.Lower PAPP-A levels.Trisomy 18 & 13:Lowered levels of both HCG PAPPP-A.2nd trimester analytes:Serum integrated screening.Accuracy of aneuploidy detection:Greater on combination with,Sonographic NT measurement.