Anti-Müllerian hormone (AMH) is a dimeric glycoprotein that inhibits the development of the Müllerian ducts in a male embryo. It is named after Johannes Peter Müller. AMH is a protein hormone structurally related to inhibin and activin, and a member of the transforming growth factor-β (TGF-β) family. It is present in fish, reptiles, birds, marsupials, and placental mammals.In mammals AMH is secreted by Sertoli cells of the testes during embryogenesis of the fetal male and prevents the development of the mullerian ducts into the uterus and other mullerian structures. The effect is ipsilateral, that is each testis suppresses Müllerian development only on its own side. In humans this action takes place by 8 weeks gestation. In female embryogenesis the absence of AMH allows for the development of upper vagina, uterus and cervix, and oviducts.