<prompt> Beta HCG is detected earliest by which day of conception?8 days15 days21 days30 days  <response>: Ans. is a i.e., 8 days Summary of pregnancy tests Beta HCGTestTest sensitivityTime takenInferencePositive onImmunological tests UrineAgglutination inhibition test Latex test0.5 - 1 IUml urine2 minutesAbsence of agglutination2 day after missed periodDirect latex agglutination test0.2 IUml urine2 minutesPresence of agglutination2-3 days after missed periodTwo-site sandwitch immunoassay membrane ELISAcard test30 - 50 mIUml urine4-5 minutesColour bands in control as well as test windowOn the first day of the mi ssed period 28th day of cycleELISA1 -2 mIUml2 - 4 hours 5 days before the first missed periodRadio - immunoassayBeta unit0.002 IUml3 - 4 hours 25th day of cycleImmunoradiometric assay IRMA0.05mIUmlserum30 minutes 8 days after conception 