Micropenis

Growth of the penis both before birth and during childhood and puberty is strongly influenced by testosterone and, to a lesser degree, the growth hormone. However, later endogenous hormones mainly have value in the treatment of micropenis caused by hormone deficiencies, such as hypopituitarism or hypogonadism.

Regardless of the cause of micropenis, if it is recognized in infancy, a brief course of testosterone is often prescribed[4] (usually no more than 3 months). This usually induces a small amount of growth, confirming the likelihood of further growth at puberty, but rarely achieves normal size. No additional testosterone is given during childhood, to avoid unwanted virilization and bone maturation. (There is also some evidence that premature administration of testosterone can lead to reduced penis size in the adult.)[5]

Testosterone treatment is resumed in adolescence only for boys with hypogonadism. Penile growth is completed at the end of puberty, similar to the completion of height growth, and provision of extra testosterone to post-pubertal adults produces little or no further growth.

Because hormone treatment rarely achieves average size, several surgical techniques similar to phalloplasty for penis enlargement have been devised and performed; but they are not generally considered successful enough to be widely adopted and are rarely performed in childhood.

In extreme cases of micropenis, there is barely any shaft, and the glans appears to sit almost on the pubic skin. From the 1960s until the late 1970s, it was common for sex reassignment and surgery to be recommended. This was especially likely if evidence suggested that response to additional testosterone and pubertal testosterone would be poor. With parental acceptance, the boy would be reassigned and renamed as a girl, and surgery performed to remove the testes and construct an artificial vagina. This was based on the now-questioned idea that gender identity was shaped entirely from socialization, and that a man with a small penis can find no acceptable place in society.

Johns Hopkins Hospital, the center most known for this approach, performed twelve such reassignments from 1960 to 1980, most notably that of David Reimer (whose penis was destroyed by a circumcision accident), overseen by John Money. By the mid-1990s, reassignment was less often offered, and all three premises had been challenged. Former subjects of such surgery, vocal about their dissatisfaction with the adult outcome, played a large part in discouraging this practice. Sexual reassignment is rarely performed today for severe micropenis (although the question of raising the boy as a girl is sometimes still discussed.)[6] (See "History of intersex surgery" for a fuller discussion.)