Louise Caselotti, who worked with Callas in 1946 and 1947, prior to her Italian debut, felt that it was not the heavy roles that hurt Callas's voice, but the lighter ones. Several singers have suggested that Callas's heavy use of the chest voice led to stridency and unsteadiness with the high notes. In his book, Callas's husband Meneghini wrote that Callas suffered an unusually early onset of menopause, which could have affected her voice. Soprano Carol Neblett once said, "A woman sings with her ovaries—you're only as good as your hormones."