Main function of B HCG:
Ans: a (Maintain corpus luteum)Ref: William's Obstetrics, 23rd ed., Chapter 3Both alpha- and beta-chain synthesis of hCG are regulated separately. A single gene located on chromo- some 6 encodes the alpha-subunit for hCG, LH, FSH, and TSH. There are seven separate genes on chromosome 19 for the beta-hCG- beta-LH family.The best-known biological function of hCG is the so-called rescue and maintenance of function of the corpus luteum-- that is, continued progesterone production.Progesterone-producing life span of a corpus luteum of menstruation could be prolonged perhaps for 2 weeks by hCG administration.Maximum plasma hCG concentrations are attained well after hCG-stimulated corpus luteum secretion of progesterone has ceased. Specifically, progesterone luteal synthesis begins to decline at about 6 weeks despite continued and increasing hCG production.Before 5 weeks, hCG is expressed in both syncytiotrophoblast and cytotrophoblast. Later, when maternal serum levels peak, hCG is produced almost solely in syncytiotrophoblasts.
Maintain corpus luteum
Stimulate decidua
Initiate implantation
initiate breast growth
Endocrine Control of the Menstrual Cycle