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¡ Both blood and urine tests can be qualitative, answering the question “Is the patient pregnant?”
¡ But only blood can be quantitative, answering the question “How pregnant is the patient?”
Human chorionic gonadotropin is detected in the maternal blood as early as 23 days menstrual age.
Human chorionic gonadotropin can be measured using several methods.
¡ Most assays for hCG are now calibrated against the Third International Standard, but some may still use the Second International Standard.
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