A human chorionic gonadotropin (hCG) urine test is a pregnancy test.
A pregnant woman’s placenta produces hCG, also called the pregnancy hormone. If you’re pregnant, the test can usually detect this hormone in your urine about 10 days after your first missed period. This is when the fertilized egg attaches to the uterine wall. During the first 8 to 10 weeks of pregnancy, hCG levels normally increase very rapidly. These levels reach their peak at about the 10th week of pregnancy, and then they gradually decline until delivery.