Broncos hooker Brittany Breayley.

Reigning Dally M medallist Brittany Breayley has opened up on her decision to leave the Broncos for St George Illawarra ahead of the NRL Holden Women's Premiership season.

Breayley's decision to depart the defending premiers sent shockwaves through the women's game but the passionate Queenslander said the club's decision not to renew coach Paul Dyer's contract, along with some self-pressure and her battle with some personal demons, all played their part.

The 28-year-old from Mackay will join former Broncos teammates Kimiora Nati, Teuila Fotu-Moala and Ngatokotoru Arakua at the Dragons in a major shake-up to the competition in its second season.

But Breayley indicated it was not a pact decision between the quartet and that she made the move after receiving a call from Dragons coach Daniel Lacey out of the blue.

"I never saw it coming," Breayley told NRL.com.

"I only ever saw myself playing for the Broncos, it's such a great club and Brisbane is home for me.

"The loss of Pauly D was a shock I guess but that wasn't the only reason why I left. There was a lot to consider being a female athlete with a job to uphold and a lot of other struggles in life.

Women's Dally M Medal winner Brittany Breayley.
Women's Dally M Medal winner Brittany Breayley. ©NRL Photos

"The opportunity was there for me and given a few things in my life that I've been working on, some personal demons, I took this as a bit of a blessing and feel it's the right decision for me.

"The Broncos were obviously really disappointed and I'll miss a lot of the girls but in the end I went with my heart."

It will be the first time she'll be able to work with Lacey, who is highly regarded in the Illawarra region and was assistant coach to the NSW City side in June.

Breayley said she felt enormous pressure to live up to the tag of being dubbed the best female player in the NRLW after taking out the prestigious medal last season.

"There is always some pressure. I came back to the field after injury and didn't have the greatest of returns," Breayley said.

"I haven't been playing the greatest footy. I'm always my biggest critic and have put a lot of pressure on myself and I want to redeem that and get back on track with a fresh start at the Dragons."

Breayley will meet her new teammates on Sunday for a club induction day before relocating to Wollongong in August for the eight-week period.