Olympic medallist Amy Tinkler says she made a formal complaint to British Gymnastics in December 2019 about her "experiences as a club and elite gymnast".
The 20-year-old, who won floor bronze at Rio 2016, says she is "no closer to having any feedback or outcome".
In a statement on social media on Tuesday, Tinkler, who retired in January, said she was "heartbroken".
It comes amid widespread allegations of abuse within the sport in Britain.
British Gymnastics said Tinkler's case is "at an advanced stage", adding that she has been kept "fully informed" and provided with the "appropriate support".
Tinkler was Great Britain's youngest medallist at Rio 2016, when she won bronze aged 16, and also won one world medal, three European medals and 10 British titles during her career.
She said: "I'm so proud of my fellow gymnasts who have shared their stories. I know how hard it is and your bravery has been a shining light and inspiration in dark and troubling times for the sport we love.
"I submitted a formal complaint to British Gymnastics in December 2019. It was an account of my experiences as a club and elite gymnast, and the experiences I shared were the reason for my retirement in January, not a physical injury as was suggested by some at the time.
"After eight months, I'm no closer to having any feedback or outcome.
"It took a lot of support and counselling to build up the courage to tell my story. I hope someone now listens to us."
British Gymnastics told BBC Sport: "British Gymnastics received formal notification of a complaint from Amy Tinkler in December 2019 and she provided full details of this complaint to us on 10 March 2020, which then allowed the investigation to proceed.
"It is at an advanced stage and we have kept Amy Tinkler fully informed and provided her with the appropriate support and we will continue to do so.
"We can make no further comment at this stage in the process."
Last week British Gymnastics announced an independent review will take place following allegations of mistreatment from a number of athletes in recent days.
Dame Tanni Grey-Thompson, a cross-bench peer and an 11-time Paralympic gold medallist, said: "There's a duty to those athletes to do something to bring about change.
"We love sport in this country, we love seeing them win medals, we don't like seeing athletes broken and to me there are some simple solutions to make sure we protect them as much as we can.
"I think holding any inquiry to account and really checking it's independent is important because if the athletes don't understand the nature of the independence, they wont come forward."