Clinical Significance

Similarly to LH (Luteinizing hormone), FSH (Follicle‑stimulating hormone) and TSH (Thyroid‑stimulating hormone), human chorionic gonadotropin (hCG) is a member of the glycoprotein family and consists of 2 subunits (α‑ and β‑chains) which are associated to form the intact hormone. The α‑chains in all four of these glycoprotein hormones are virtually identical, whereas the β‑chains have greatly differing structures and are responsible for the respective specific hormonal functions. 

hCG is produced in the placenta during pregnancy. In non‑pregnant women, it can also be produced by tumors of the trophoblast, germ cell tumors with trophoblastic components and some non‑trophoblastic tumors. 

Human chorionic gonadotropin consists of a number of isohormones with differing molecular size. The biological action of hCG serves to maintain the corpus luteum during pregnancy. It also influences steroid production. The serum of pregnant women contains mainly intact hCG.

_{Source: Roche cobas Elecsys HCG+β method sheet, V 4.0 2024-04}