Human chorionic gonadotropin (hCG) is a hormone produced by the placenta after the embryo adheres to the wall of the uterus. It's also called the "pregnancy hormone" . The urine pregnancy test can usually detect this hormone about ten days after the first missed period. During the first 8 to 10 weeks of pregnancy, hCG levels increase very rapidly, and they reach their peak at about the 10th week of pregnancy. The presence of hCG in the urine is considered a positive sign of pregnancy.
