[4] LESSON 9: PREGNANCY AND DRUG TESTING Flashcards
May be performed using urine or blood
PREGNANCY TESTING
Involves the detection of human chorionic gonadotropin (hCG)
PREGNANCY TESTING
PREGNANCY TESTING
Specimen requirements:
[?]
Specific gravity should be [?]
First morning urine
≥ 1.015
Synthesized and secreted by placental trophoblast cells
Human Chorionic Gonadotropin (hCG)
Helps maintain the vascular integrity of the endometrium with an adequate blood supply until placental synthesis of progesterone begins
Human Chorionic Gonadotropin (hCG)
Glycoprotein hormone with two non-identical subunits (α and β)
Human Chorionic Gonadotropin (hCG)
: structurally similar with that of LH, FSH and TSH
α-chain
: unique to hCG
β-chain
Secreted in the urine within 2 to 3 days after implantation
α and β
Rise rapidly after conception and remain elevated, peaking in the first timester of pregnancy (8-10 weeks: about 100,000 IU/L)
α and β
- Detect pregnancy and its abnormalities (ectopic and molar pregnancies)
Human Chorionic Gonadotropin (hCG)
- Screening for Down’s syndrome and Edward’s syndrome
Human Chorionic Gonadotropin (hCG)
- Monitor the course of a patient with trophoblastic cancer
Human Chorionic Gonadotropin (hCG)
Laboratory Detection
- Rapid Test Kits
- Rapid Test Kits
False negative:
dilute urine
- Rapid Test Kits
False positive:
large amounts of blood, protein or bacteria; presence of certain drugs (phenothiazine)
- Rapid Test Kits
Principle:
enzyme immunoassay (EIA) or immunochromatographic
BIOLOGICAL PREGNANCY TESTS
Ascheim-Zondek
Immature female mice
Ascheim-Zondek
subcutaneous
Ascheim-Zondek
Galli-Mainini
Frank-Berman
Formation of hemorrhagic follicles and corpora lutea
Ascheim-Zondek
Mature virgin female rabbits
Friedman
Marginal ear vein
Friedman
Hyperemic uterus and corpora hemorrhagica
Friedman
Female toad ( Xenopus laevis )
Hogben