HCG is a glycoprotein hormone secreted by the developing placenta during pregnancy. The concentration of HCG in serum is approximately equal to the concentration in urine. The concentrations of HCG in urine and serum continue to rise during the first trimester of pregnancy to as high as 100, 000mIU/ml. HCG appears in serum and urine shortly after conception, and continues to increase during the early stages of pregnancy, making it an excellent indicator for the detection of pregnancy.
