The human chorionic gonadotropin detection kit (colloidal gold method) is also called a pregnancy test card, which is the card-shaped test paper that we often call the early pregnancy test paper. Detection principle: It is a reliable indicator to assist the clinical judgment of pregnancy by detecting the concentration of HCG in the urine to confirm whether a woman is pregnant. HCG, human chorionic gonadotropin, is a glycoprotein produced by the placenta during pregnancy and can be excreted from the urine through the glomerulus.