Along with luteinizing hormone (LH), chorionicgonadotropin (hCG), and thyroid-stimulating hormone(TSH), follicle-stimulating hormone (FSH) belongs to thepituitary glycoprotein hormone family. 1 The alpha chain ofthe pituitary glycoprotein hormone family is shared by allmembers, whereas the beta chain is encoded by a differentgene. The beta subunit of follicle stimulating hormone isencoded by the FSHB gene. FSH is necessary forspermatogenesis, Sertoli cell proliferation, and ovarianfolliculogenesis. Since anti-FSH identifies cells that produceFSH (gonadotrophs), it is a helpful marker in thecategorisation of pituitary neoplasms.