Male model Andrej Pejic has undergone sex reassignment surgery.

The 22-year-old Bosnia-born catwalk star has changed her name to Andreja as she takes the first steps towards becoming a woman.

The once-famous androgynous model underwent surgery quietly a few months ago, but now Pejic is ready to reveal her journey to the public.

She tells People.com, "I want to share my story with the world because I think I have a social responsibility. I hope that by being open about this, it becomes less of an issue."

She adds, "I always dreamed of being a girl. One of my earliest memories is spinning around in my mom's skirt trying to look like a ballerina... I kept my dreams and my imagination to myself and became pretty good at acting as a boy. But I was hiding who I was."

Growing up in Melbourne, Australia, Pejic discovered he wasn't alone when he was just 13, adding, "I went into the library and typed 'sex change' into Google and my life changed. The Internet gave me the sense that there were words to describe my feelings and medical terms."

Pejic launched a career as an androgynous model for the likes of Jean-Paul Gaultier in 2011, but she "reevaluated things" at the beginning of 2013: "I was proud of my gender non-conforming career, but my biggest dream was to be comfortable in my own body. I have to be true to myself and the career is just going to have to fit around that."

So she began researching sex reassignment surgery and then came to America to undergo the procedure: "I was happy the moment had come... Now I'm more comfortable than ever. I feel at a 100 per cent."