Following implantation, the syncytiotrophoblast gives rise to the placenta.
Some cancerous tumors produce this hormone; therefore, elevated levels measured when the patient is not pregnant can lead to a cancer diagnosis.However, it is not known whether this production is a contributing cause or an effect of tumorigenesis.
The pituitary analogue of hCG, known as luteinizing hormone (LH), is produced in the pituitary gland of males and females of all ages.
As of December 6, 2011, the FDA has prohibited the sale of "homeopathic" and over the counter hCG diet products and declared them fraudulent and illegal. source : wikipedia.org
