LAUSANNE, Switzerland -- Two Chinese female weightlifters have lost their appeals against being stripped of their 2008 Beijing Olympic gold medals for doping.

The Court of Arbitration for Sport said Monday that the IOC was right to disqualify Cao Lei from the 75-kilogram class and Liu Chunhong in the 69-kilo event at their home Summer Games.

Both tested positive for GHRP-2, which stimulates production of growth hormone, in reanalysis last year of their samples taken in Beijing. Liu also tested positive for sibutramine, a banned stimulant.

Because the cases were similar, the IOC disciplinary commission urged the International Weightlifting Federation to investigate Chinese team coaches and officials.

Weightlifting risks being dropped from the 2024 Olympics due to longstanding doping problems, and the International Olympic Committee has requested a "satisfactory report" from the governing body by December.

In retesting of samples from the 2008 Beijing Olympics and 2012 London Olympics, about 50 doping cases have been found and more than 25 medals were stripped. Most involved steroids used by athletes from the former Soviet Union republics.

The cases of Cao and Liu involved a growth hormone releasing peptide which could not be detected with the testing technology available in 2008.

The lawyer for both athletes argued to CAS that the cases should be dropped because GHRP-2 was not specifically named in the prohibited list of substances published by the World Anti-Doping Agency.

The court's single judge accepted the IOC case that a section of the list relating to "hormones and related substances" applied in these cases.

Even without three gold medals stripped from Chinese lifters, the home team still won five of the 15 titles in Beijing.