There are two pituitary gonadotropins, luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Their general biological roles are the stimulation of testicular and ovarian functions via the regulation of gametogenesis and steroid hormone synthesis in the gonads. Synthesis and release of FSH is triggered by the arrival of gonadotropin-releasing hormone (GnRH) from the hypothalamus. LH is synthesized similarly within the pituitary gland, requiring the same stimulus as FSH, the GnRH from the hypothalamus. Both hypothalamic abnormalities and intrinsic pituitary abnormalities can cause an abnormal FSH/LH response to GnRH. Hypersecretion of gonadotropins are often associated with pituitary adenomas [DS:H01102] and central precocious puberty [DS:H00937]. Hyposecretion of gonadotropins [DS:H00255H01700] in premenopausal women leads to absent menstrual cycles, infertility, vaginal dryness, and loss of some female characteristics. In men, this deficiency leads to impotence, atrophy of the testes, decreased sperm production, infertility, and loss of some male characteristics.
