In 1979 she won at the Track Central American and Caribbean Championships in Guadalajara. More titles there they took in 1981, 1985, 1989. The Central American and Caribbean Games, she won in 1982 and 1986, the gold and the silver medal in 1990. Three times she was at Second Pan-American Games (1983, 1987, 1995).
In 1985, she won at the IAAF World Indoor Games in Paris a bronze medal in the high jump. She shared it in third place with two other jumpers. In 1989, she achieved her personal best of 2.04 m. Previously, only three athletes - Stefka Kostadinowa, Lyudmila Andonowa and Tamara Bykova - ever skipped a greater height.
At the 1992 Olympics in Barcelona Costa came in sixth. The major international success she succeeded at the World Athletics Championships in Stuttgart in 1993. With a height of 1.97 m skipped, she won the silver medal behind her compatriot Ioamnet Quintero (1.99 m ) and before the same height Sigrid Kirchmann from Austria.
Silvia Costa is 1,79 m tall and weighed in their active time 60 kg.
- High jump: 2,04 m, September 9, 1989, Barcelona Hall: 1.96m, February 3, 1985, Turin