Luteinizing hormone A pituitary glycoprotein hormone that stimulates development of ovarian follicles to the preovulatory stage, induces ovulation, and causes the primary oocyte to complete the first meiotic division.
In addition to its synthesis during normal pregnancy, trophoblastic disease, or cancer, a small amount of hCG is normally produced by the pituitary gland in conjunction with the structurally similar glycoprotein hormones luteinizing hormone, follicle-stimulating hormone (FSH), and thyroid-stimulating hormone (3, 4).
Hyperglycosylated human chorionic gonadotropin (HhCG) is a glycoprotein hormone secreted during embryonic implantation and trophoblast invasion of the uterine wall and is an early marker of pregnancy (1).
The heterodimeric placental hormone human chorionic gonadotropin (hCG)  is a widely studied member of the glycoprotein hormone family that includes luteinizing hormone, thyroid-stimulating hormone, and follicle-stimulating hormone.
Common epithelial tumors of the urogenital tract frequently express the free [beta]-subunit of human chorionic gonadotropin (hCG[beta])  with no concomitant expression of its heterodimer partner, the common [alpha]-subunit of the glycoprotein hormone (1-4).