A positive urine test for HCG indicates pregnancy. HCG, short for human chorionic gonadotropin, is a glycoprotein secreted by the trophoblast cells of the placenta. A woman forms an embryo after the fertilized egg moves into the uterine cavity and beds there. During the process of development and growth into a fetus, the placental syncytiotrophoblast cells can produce a large amount of HCG, which is excreted into the urine through the pregnant woman’s blood circulation. HCG levels in the serum and urine can rise rapidly at 1-2.5 weeks of pregnancy and reach a peak at 8 weeks of pregnancy. Clinically, HCG levels in urine are detected by immunological methods using pregnant women’s urine, and if they exceed the normal values, pregnancy is indicated.