gonadotropinsfolliclestimulating

Gonadotropins are glycoprotein hormones that regulate the function of the gonads, the ovaries and testes. In humans, the primary endogenous gonadotropins are follicle-stimulating hormone (FSH) and luteinizing hormone (LH), produced by the anterior pituitary, and placental chorionic gonadotropin (hCG), which shares activity with LH. Exogenous gonadotropins used in medicine include urinary-derived preparations containing FSH and LH activity (often referred to as menotropins or hMG) and recombinant forms of FSH and LH. hCG is used pharmacologically to trigger ovulation in fertility treatments.

Gonadotropins are heterodimeric glycoproteins composed of alpha and beta subunits; the alpha subunit is common to several hormones, while the beta subunits determine receptor specificity. The FSH receptor (FSHR) and the LH/hCG receptor (LHCGR) are G protein–coupled receptors that stimulate intracellular cAMP signaling. In the ovary, FSH promotes follicular growth and estrogen production, while LH supports ovulation and corpus luteum formation with progesterone production. In the testis, FSH acts on Sertoli cells to support spermatogenesis, in concert with LH-stimulated testosterone production by Leydig cells.

Secretion is regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus, with negative feedback from sex steroids and inhibins modulating pituitary output. Clinically, gonadotropins are used in infertility treatment, controlled ovarian stimulation, and management of hypogonadism. Adverse effects can include ovarian hyperstimulation syndrome and an increased risk of multiple gestations; overall safety depends on indication, dosing, and monitoring.