Whistleblower soldier Bradley Manning decided to announce that he wanted to live as a woman the day after he was sentenced because a military prison said it would not provide hormone treatment, his lawyer said.
David Coombs said Manning, who now wants to be known as Chelsea, had known for a long time he would make such a statement, but "she wanted, essentially, for the media surrounding the trial to dissipate".
Manning did not want people to think the statement was insincere. "People might think it was an effort to get further attention," said Mr Coombs, of Providence, Rhode Island.
On Bradley Manning, US Army says it does not provide hormone therapy, sex-assignment surgery for gender identity disorder
The lawyer for Bradley Manning, who wants to be known as Chelsea Manning and live life as a woman, said he would do "everything in [his] power" to make Fort Leavenworth provide the soldier with the therapy she has requested.
Julian Assange has hailed a "significant tactical victory" in the case of Bradley Manning after the former US soldier was handed a 35-year sentence.
In a statement, he said: "While the defence should be proud of their tactical victory, it should be remembered that Mr Manning’s trial and conviction is an affront to basic concepts of Western justice...
"Mr Manning’s treatment has been intended to send a signal to people of conscience in the US government who might seek to bring wrongdoing to light. This strategy has spectacularly backfired, as recent months have proven.
"Instead, the Obama administration is demonstrating that there is no place in its system for people of conscience and principle. As a result, there will be a thousand more Bradley Mannings."