Stanley of England in action against Scotland during the Tokyo Sevens in March 2014.
The 23-year-old, from Essex, becomes the first out professional English rugby union player.
Stanley, who comes from a famous rugby family, played for Saracens, as well as for England U16 and U18. He is currently playing for Ealing Trailfinders.
In the Sunday Times interview, Stanley, who realised he may have been gay at age 10 or 11, talked about how he had felt suicidal in the past because of the struggle with his sexuality.
“I was standing on a bridge about four or five years ago, overlooking a motorway in Essex,” he said.