[3] Her best result in singles was the quarterfinals of the 1933 Wimbledon Championships where she lost to second-seeded Dorothy Round, the eventual runner-up.
[4] That same year, she partnered with Madzy Rollin Couquerque to reach the third round of the women's doubles competition.
In the 1935 mixed doubles competition, she and partner Don Turnbull lost to the top-seeded pair of Hilde Krahwinkel Sperling and Gottfried Von Cramm in the quarterfinals.
In 1930, Valerio played against Phyllis Satterthwaite in the final of the Bordighera Championship on the Italian Riviera.
[6] In 1931, Valerio won the singles title at the Italian Championships in Milan, defeating Dorothy Andrus in the three-set final.