Assessment of seminiferous tubule function (anti-müllerian hormone).

Anti-müllerian hormone (AMH) is specifically produced by Sertoli cells in the male. The testes express a high level of AMH from early fetal life, driven by the transcription factors SOX9, SF1, WT1 and GATA4, until puberty, when AMH is downregulated by testosterone and meiosis. When androgen negative effect is absent, follicle-stimulating hormone increases the secretion of AMH. Serum AMH determination is useful in the evaluation of children with non-palpable gonads, with or without ambiguous genitalia. It signals the existence of functional testicular tissue and allows a distinction to be made between gonadal dysgenesis and dissociated tubular-interstitial dysfunction. Serum AMH is a useful marker in the follow-up of male patients with precocious puberty or hypogonadotrophic hypogonadism, as well as of patients with sex cord stromal tumours of the gonads. Finally, AMH determination on the seminal plasma of men with non-obstructive azoospermia may be used as a marker of the existence of testicular spermatozoa when intracytoplasmic sperm injection is considered.