Los Angeles: Venus Williams voiced dismay after Russian hackers who broke into the World Anti-Doping Agency database released details of her confidential medical records.
The veteran tennis superstar was one of four US athletes targeted by Russian hacking group Fancy Bears in a cyber-attack that has been widely criticized.
Sister Serena Williams, US Olympic gymnast Simone Biles and women's basketball player Elena Delle Donne also saw their records published by the group.
"I was disappointed to learn today that my private, medical data has been compromised by hackers and published without my permission," Williams said in a statement.
The released records detailed examples of where Williams had applied for therapeutic use exemptions (TUEs) which allowed her to use certain medications banned by Wada.
The use of exemptions is standard practice in the sports world and is not regarded as a doping offence.
"The applications for TUEs under the Tennis Anti-Doping program require a strict process for approval which I have adhered to when serious medical conditions have occurred," Williams said.
"I am one of the strongest supporters of maintaining the highest level of integrity in competitive sport and I have been highly disciplined in following the guidelines set by Wada, USADA (US Anti-Doping Agency), the ITF (International Tennis Federation) and collectively the Tennis Anti-Doping Program."