Fetal exposure to DES is thought to be a major contributing factor to becoming MTF Transgender, and as you likely know as is the same for females exposed to DES while in the womb, can lead to other health issues. Im not aware that my Mom took DES while she was pregnant w/ me, but we will never know. As to when began my own transition, usaually say that it was several years ago when I began HRT. But in retrospect I could easily say it was back when I was 4 ,and saw a female playmates genitals for the very first time, and wished that I had ones that looked like that, and not the ugly "thing" I was born w/. I could also say it was a a few later when I used to play w/ my Grandmas cosmetics and costume jewelry. Or maybe when I was 1, the first time I tried on some of my Moms clothes. Or a few years later when I had developed a shameful "fetish" for lingerie that I kept hidden for many many years. Or maybe it was st the ripe old age of 55, the first time I tried on a dress and the feeling were anything but sexual. It was more a feeling of be comfortable for who I was for once.