Urine Pregnancy Test- Human Chorionic Gonadotropin (HCG) Testing

From the earliest stage of development, the placenta produces hormones, either on its own or in conjunction with the fetus. The very young placental trophoblast produces appreciable amounts of the hormone human chorionic gonadotropin (hCG), which is excreted in the urine. This hormone is not found in the urine of men or of normal, young, non-pregnant women. 

Increased urinary hCG levels form the basis of the tests for pregnancy; hCG is present in blood and urine whenever there is living chorionic/placental tissue. hCG is a glycoprotein made up of alpha and beta subunits with 237 amino acids. The beta subunit is the most sensitive and specific test for early pregnancy. hCG can be detected in the urine of pregnant women 26 to 36 days after the first day of the last menstrual period (ie, 5 to 7 days after conception). Pregnancy tests should return to negative 3 to 4 days after delivery. 

Urine Dipstick Testing and Possible Reaction Interference

Although laboratory facilities allow for a wide range of urine tests, some types of tablet, tape, and dipstick tests are available for UA outside the laboratory setting. They can be used and read directly by patients and clinicians.

Similar in appearance to pieces of blotter paper on a plastic strip, dipsticks actually function as miniature laboratories. Chemically impregnated reagent strips provide quick determinations of pH, protein, glucose, ketones, bilirubin, hemoglobin (blood), nitrite, leukocyte esterase, urobilinogen, and specific gravity. The dipstick is impregnated with chemicals that react with specific substances in the urine to produce color-coded visual results. The depth of color produced relates to the concentration of the substance in the urine. Color controls are provided against which the actual color produced by the urine sample can be compared.

Sysmex UF1000i Analyzer- Urinalysis Automation

*Note: This site has no affiliation with Sysmex and we just want to promote the product here as we know this can improve the quality of laboratory diagnosis. If we violated anything, please CONTACT US and we will remove this post immediately.

image courtesy of: www.sysmex.com