Nancy Yareli Contreras Reyes (born January 20, 1978, in Ciudad de México, Distrito Federal) is a female track cyclist from Mexico, who represented her native country twice at the Summer Olympics: 1996 and 2004. She won a bronze medal in the 1995 Pan American Games in Mar del Plata, Argentina.
Contreras won the 500m time trial gold during the 1998 Central American and Caribbean Games, but failed the doping control with Pseudoephedrine and her medal was removed.[1][2]
