Pregnancy testing

• What do pregnancy tests detect?

  The hormone hCG that is found in the urine of pregnant women
• what does the hormone hCG stand for ?

  human chorionic gonadotropin
• What does the application area contain?


  Antibodies for hCG bound to a coloured bead (blue)
• what colour is the coloured bead?

  blue
• What happens when urine is applied to the application area?


  • Any hCG will bind to the antibody on the beads, forming an antigen-antibody complex
  • The urine moves up the stick to the test strip, carrying any beads with it
• What does the test strip contain?


  Antibodies to hCG that are stuck in place/ IMMOBILISED
• What happens if there is hCG present?

  The test strip turns blue because the immobilised antibody binds to any hCG - concentrating the hCG-antibody complex with the blue beads attached
• What happens if no hCG is present?

  The beads will pass through the test area without binding to anything, so it will not go blue