Final answer:
A CLIA waived pregnancy test detects the presence of human chorionic gonadotropin (hCG), a hormone produced early in pregnancy. The lateral flow test shows a color band on the test line in the presence of hCG, while the control line indicates if the test is valid.
Step-by-step explanation:
A CLIA waived pregnancy test is based on the detection of human chorionic gonadotropin (hCG). This hormone serves as a biomarker for pregnancy because it is initially produced by the embryo and later by the placenta. The lateral flow method used in these tests involves a test strip that has both a test line and a control line. When urine containing hCG flows along the test strip, the hormone binds to the antibodies conjugated to colored particles. If hCG is present, a color band appears on the test line in addition to the control line, indicating a positive result for pregnancy. The control line, which should always show a color band if the test is functioning correctly, binds to the beads without the presence of the hormone. This dual-band result confirms the test's validity.