Transgender does not mean having a sex change operation. Statistics say that somewhere between 66 and 90 percent of transgender people do not get sex change operations[1][2], and 40% have any no medical treatments at all (hormonal, surgical... anything) related to transitioning their gender[1].
[1] http://www.thetaskforce.org/static_html/downloads/reports/re...
[2] http://www.nytimes.com/2011/03/23/nyregion/23gender.html