Coelho began studying architecture at a college in Rio de Janeiro, but she soon decided she would develop her singing career in Europe.
She also appeared as a guest artist in several opera houses, as in the Teatro Regio di Torino, where she sang in Lulu, and also in Aachen and in the Vienna Volksoper.
In 1988, she sang the roles of Giulietta, in The Tales of Hoffmann, at the Festival of Bregenz, and of Donna Elvira at the Theatro Municipal in Rio de Janeiro.
At that house, she performed dozens of roles, including: Maria in Maria Stuarda, Giulietta in The Tales of Hoffmann, Elettra in Idomeneo, Donna Anna in Don Giovanni, Salomé in Hérodiade, Hélène in Verdi's Jérusalem, Elena in I Vespri Siciliani, Abigaille in Nabucco, Tosca, Madama Butterfly, Liù in Turandot, Lady Macbeth, Lina in Stiffelio, Maddalena in Andrea Chénier and many other roles.
She also performed as a guest artist at the Vienna Volksoper as Tatiana in Eugene Onegin and as Abigaille, in 1992; at the Bavarian State Opera and at the Berlin Staatsoper as Salome, in 1995; at La Scala, in Milan, as Madama Butterfly, in 1996; at the Opéra Bastille, in Paris, as Salome, in 1996; and in other important opera houses all around the world, from Manaus, in Brazil, to Tokyo.