Human chorionic gonadotropin

Chorionic gonadotropin, alpha polypeptide
Identifiers
Symbol	CGA
Alt. symbols	FSHA, GPHa, GPHA1, HCG, LHA, TSHA
NCBI gene	1081
HGNC	1885
OMIM	118850
RefSeq	NM_000735
UniProt	P01215
Other data
Locus	Chr. 6 q14-q21
Search for Structures Swiss-model Domains InterPro

Human chorionic gonadotropin (hCG) is a hormone for the maternal recognition of pregnancy produced by trophoblast cells that are surrounding a growing embryo (syncytiotrophoblast initially), which eventually forms the placenta after implantation.^[1][2] The presence of hCG is detected in some pregnancy tests (HCG pregnancy strip tests). Some cancerous tumors produce this hormone; therefore, elevated levels measured when the patient is not pregnant may lead to a cancer diagnosis and, if high enough, paraneoplastic syndromes, however, it is unknown whether this production is a contributing cause or an effect of carcinogenesis. The pituitary analog of hCG, known as luteinizing hormone (LH), is produced in the pituitary gland of males and females of all ages.^[1][3]

Various endogenous forms of hCG exist. The measurement of these diverse forms is used in the diagnosis of pregnancy and a variety of disease states.^[1] Preparations of hCG from various sources have also been used therapeutically, by both medicine and quackery. As of December 6, 2011^[update], the United States Food and Drug Administration has prohibited the sale of "homeopathic" and over-the-counter hCG diet products and declared them fraudulent and illegal.^[4][5][6]

Beta-hCG is initially secreted by the syncytiotrophoblast.^{[citation needed]}