The Autobio human chorionic gonadotropin (hCG) chemiluminescence immunoassay (CLIA) kit is intended for the quantitative determination of hCG concentration in human serum.
Human chorionic gonadotropin (hCG) is a sialoglycoprotein with a molecular weight of approximately 46,000 daltons. hCG is initially secreted by the trophoblastic cells of the placenta shortly after implantation of the fertilized ovum into the uterine wall. The rapid rise in serum levels of hCG after conception makes it an excellent marker for early confirmation and monitoring of pregnancy.
The placental hormone, hCG, is similar to luteinizing hormone (LH), follicle stimulating hormone (FSH), and thyroid stimulating hormone (TSH). All are glycoproteins consisting of two noncovalently bound dissimilar subunits, designated alpha and beta, with attached carbohydrate sidechains. The alpha subunits of these glycoproteins are very similar. In contrast, the beta subunit portions determine the biological and immunochemical specificities. The beta subunits of hCG and LH exhibit considerable homology in amino acid content. Amino acid residues specific for the beta subunit of hCG confer the immunochemical specificity.
According to the literature, circulating hCG typically reaches levels of approximately 2,000mIU/mL a month after conception. In the normal second-trimester maternal sera, the level of intact hCG ranges from 20,000 mIU/ml to 50,000mIU/ml. After the third month a gradual decline sets in. Following delivery, the hCG level normally undergoes rapid descent, reaching nonpregnant concentrations some two weeks later.
Ectopic pregnancies and pregnancies terminating in spontaneous abortion tend to have lower than normal circulating hCG levels, while somewhat higher levels are often seen in multiple pregnancies.
