AMH (Anti-Mullerian Hormone)
Hormonal / ReproductiveAlso known as: Anti-Mullerian Hormone, Mullerian Inhibiting Substance, MIS, Mullerian Inhibiting Factor, MIF
Mechanism
AMH is a hormone used as the gold-standard blood test for ovarian reserve in women — it tells you roughly how many eggs remain. Produced by small ovarian follicles, higher AMH means more eggs in reserve. In male fetal development, AMH causes the Mullerian ducts (which would become the uterus and fallopian tubes) to regress, which is how it got its name.
Technical detail
AMH (Anti-Mullerian Hormone) is a 140 kDa homodimeric glycoprotein of the TGF-beta superfamily. It signals through AMHR2 (a type II serine/threonine kinase receptor) which recruits type I receptors ALK2/ALK3, activating Smad1/5/8 signaling. In fetal males, Sertoli cell-derived AMH causes Mullerian duct regression via apoptosis and epithelial-mesenchymal transition. In adult females, granulosa cells of preantral and small antral follicles produce AMH, which inhibits primordial follicle recruitment and reduces follicular sensitivity to FSH. Serum AMH is a reliable, cycle-independent biomarker of ovarian reserve.