Basildon Pathology Handbook

In NORMAL pregnancy, hCG is present at low levels as early as 6 days following conception with concentrations doubling every 32-48 hours. For some women the hCG concentration reaches 25 IU/L as early as 2-3 days before the expected period and by the first day of a missed period, hCG levels often exceed 100 IU/L. ................
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