Understanding Pregnancy Tests: HCG And How It’s Detected

Understanding Pregnancy Tests: HCG And How It’s Detected

Pregnancy tests.
Answer:

Pregnancy tests are based on the presence of human chorionic gonadotropin (HCG) in urine, detected as early as 14 days after conception.

1. Biological tests:

• These are peformed on experimental animals.
  • Aschheim – zondek test:
    • Mice is used in this tests.
      Procedure:
      2 ml of urine from suspected mother is injected dialy into mice for five days.
      After it, mice are killed.
      Its ovaries are examined for the presence of corpus luteum and haemorrhages.This indicates ovulation.
  • Kupperman test.
    • It is carried out in immature rat.
    • 2 ml of urine from suspected mother is injected subcutaneously into immature rat.
    • Ovarian changes are examined after 6 hours.
  • Friedman test.
    • About 10-15 ml of urine is injected intravensouly into rabbit.
    • Ovarian changes are observed after 48 hours.
  • Hogben test.
    • About 20-30 ml of urine from suspected mother is injected into dorsal lymph sac of south African toad, xenopus levis.
    • Ovulation is checked after 12 hours.
  • Galli-mainini test.
    • 2 ml of urine from suspected mother is injected into male amphibian.
    • Explusion of spermatozoa is checked within 2 hours.

2. Immunological test:

• It is based on double antigen antibody reactions.

Immunological test Precedure:

• A drop of HCG antiserum is taken on a glass slide.
• A drop of urine from suspected mother is added to it and mixed.

Immunological test Results:

• If the urine contains HCG (present in pregnancy only), neutralization of HCG antiserum occurs.
• This doesn’t produces agglutination.
• If agglutination occurs, it means urine doesn’t contains HCG and the mother is not pregnant.

Immunological test Advantages:

• Accurate and quick metod.
• Easy to perform.
• Performed on 5th day of conception.
• Animal are not sacrificed.