http://ai.eecs.umich.edu/people/conway/TS/SRS.html#anchor41859

The above link contains graphiic diagrams and pictures of surgical procedures and resultrs of SRS anyone offended or upset by seeing graphic pictures should not open this article..

Historical Background  (An interesting extract from the above quoted link) 

 

Transsexualism is not a "modern discovery". Instead it is a not-uncommon, naturally-occurring variation in human gendering that has been observed and do***ented since antiquity. In many cultures, including native tribes in North America, transsexual individuals have long had the choice to cross-dress and live their lives as women, including taking husbands. The surgical alteration of genitalia to relieve intense cross-gender feelings was also not "invented in the twentieth century". In some cultures, even ancient ones, many transsexuals have voluntarily undergone surgeries to modify their bodies in such a way as to "change their sex".

 

The surgical methods and the effects of castration were everywhere for the ancients' to see. It's use in the domestication of animals quickly taught ancient people that removal of a human male's testicles at a young enough age would prevent his masculinization too. Such a person would forever be childlike - or "girly". These surgeries were also often forcibly done upon captive adult male slaves in order to "domesticate them" as "eunuchs". Performing such surgeries on normal post-pubertal males does not change their gender feelings or gender identity, although is lessens their sexual drives somewhat and sharply reduces their ability to develop male musculature.

 

The ac***ulating knowledge about the effects of castration was further extended to help MtF transsexuals: Untold millions of transsexuals over thousands of years have voluntarily sought and undergone surgeries vastly riskier and more dramatic in effect than mere castration. In these surgeries transsexuals are completely emasculated by total removal of the testes, penis and scrotum. In addition, the external pubic area is often roughly shaped to look like a girl's vulva. No one knows precisely how it started, but such transsexual surgeries were well known by the time of ancient Greece and especially in sexually-permissive ancient Rome, and were often traditionalized in various "religious rituals" that provided the resulting "women" with a place in society.

 

By undergoing these surgeries, young MtF transsexuals (if they survived) not only avoided becoming men, but also gained genitalia that looked somewhat like those of a woman. Although lacking vaginas and lacking the powerfully feminizing effects of female sex hormones, young transsexuals in the past could nevertheless live life better as women after undergoing such surgery.

 

Even today, very large numbers of desperate young transsexuals in India and Bangladesh run away from home to join the "Hijra" caste. To become Hijra, these teens voluntarily undergo fully emasculating surgeries under primitive conditions, just as they would have in ancient times, with only opium as an anesthetic. Most undergo the surgery in their teens shortly after the onset of puberty, with results as seen in photo below. By being castrated just early enough, many avoid the development of male secondary sex characteristics (except for the breaking and lowering of the voice), and their bodies can remain permanently soft, childlike and girly.

 

Contrary to popular myth, total external emasculation after puberty does not necessarily "de-sex" the person. Complete castration after puberty leaves the young Hijra with her newfound feelings of sexual arousal and her newfound orgasmic capabilities. While the psychological impact of such surgery would usually cripple the libido of a normal male, the effect on a young transsexual girl is usually just the opposite: The surgery can be liberating and can enable a fuller expression of her sensuality and her female libidinous feelings. Just as in the case of modern post-operative transsexual women, many Hijra can have strong feelings of sexual arousal in the inner remnants of their genitalia (even though they lack the external nerve tissue left by modern SRS, they retain the internal portions of the erectile corpora cavernosa and of course the prostate, with its spasmodic orgasmic capabilities). Although Hijra lack vaginas, many greatly enjoy (to orgasm) penetrative (anal) sexual activities with men. Because of their complete external emasculation, Hijra genitalia and pelvic regions look very "girly", and many men in India greatly enjoy lovemaking with them. The Hijra in turn accept their fate and their limited, but real, possibilities for finding at least a little bit of love as a woman in this life.