Human chorionic gonadotrophin is known as the hCG hormone secreted by the syncytiotrophoblast which originates from the fused and differentiated cytotrophoblast.
It induces the production of progesterone which helps in maintaining the pregnancy.
HCG stimulates the corpus luteum to release progesterone.
Whereas it is produced by the placenta during pregnancy stimulating progesterone secretion to increase the endometrial thickness.