Sexual differentiation in humans development can only occur when the fetal testis secretes key hormones at a critical period in early gestation. The testes begin to secrete three hormones that influence the male internal and external genitalia: they secrete anti-müllerian hormone (AMH), testosterone, and dihydrotestosterone (DHT). Anti-müllerian hormone causes the paramesonephric ducts to regress. Testosterone converts the mesonephric ducts into male accessory structures, including the epididymis, vas deferens, and seminal vesicle. Testosterone will also control the descending of the testes from the abdomen into the scrotum. Many other genes found on other autosomes, including"WT-1", "SOX9", "SF-1" also play a role in gonadal development. Females:
Transgender hormone therapy (female-to-male) to produce LH (luteinizing hormone) and FSH (follicle-stimulating hormone) which in turn cause the gonads to produce sex steroids. In adolescents of either sex with relevant indicators, GnRH analogues, such as leuprorelin can be used to suspend the advance of sex steroid induced, inappropriate pubertal changes for a period without inducing any changes in the gender-appropriate direction. GnRH analogues work by initially over stimulating the pituitary then rapidly desensitizing it to the effects of GnRH. Over a period of weeks, gonadal androgen production is greatly reduced. There is considerable controversy over the earliest age, and for how long it is