Human Follicle-stimulating hormone (FSH) is a member of glycoprotein hormones subunit beta family, whichalso includes LH, chorionic gonadotropin (CG) and thyroid-stimulating hormone (TSH). FSH and its familymembers are heterodimers consisting of non-covalently linked α- and β-subunits. They share an identical αsubunit, and β-subunits vary. FSH has a unique β-subunit (FSHβ), which confers its specific biologic activityand is responsible for interaction with the FSH-receptor which belongs to a subfamily of GPCRs calledleucine-rich-repeat-containing GPCRs (LGRs). FSH is secreted from the pituitary gland and regulatesreproduction in mammals. FSH stimulates sertoli cell proliferation in testes and supports spermatogenesis inmales, and induces the maturation of ovarian follicles in females.