Which of the following is used in first trimester screening for Down's syndrome?

Down&;s syndrome ScreeningUSG markersMaternal age - Age >35, screening test is offered.Biochemical testsUltrasonographyFirst trimester screening for Down&;s syndromePAPP-A. hCG (biochemical tests)NT (nuchal translucency) (USG)PAPP-A pregnancy-associated plasma protein-decreases in Down&;s syndromeSerum beta hCG - elevated in Down&;s syndromeNuchal translucency increases in aneuploid fetus in first trimester: 3.5 mm is significant done at 11-14 weeksSensitivity of combined NT thickness and 1st trimesterbiochemical tests is 90%.Second trimester screening for Down&;s syndromeTriple test and quadruple tests are done in second trimester at 15-20 weeksTriple test: hCG, AFP, unconjugated estriolQuadruple test: Triple test + inhibinNuchal fold thickeningMild renal pelvis dilatationEchogenic intracardiac focusEchogenic bowelSho femurSho humerus(Refer: Mudaliar and Menon&;s Clinical Obstetrics, 11th edition, pg no: 466)