In 1907 Leginska married the composer Emerson Whithorne, whom she had met when they both studied in Vienna. They would sometimes perform together, with him playing the second part in two-piano pieces on her recitals and from the time they married through 1909 him serving as her concert manager. He later wrote music criticism for "Musical America" and "Paul Mall Gazette", and as a composer, he had his music performed frequently in the 1920s and 1930s. She and Emerson Whithorne had one son, Cedric Whithorne, born in September 1908 after the couple returned from visiting Whithorne's native United States. They did so at least once prior to their divorce, traveling to Cleveland, OH where Leginska make her unofficial American debut in Cleveland's Hippodrome, a vaudeville theater. Nonetheless, the couple separated in 1910 and divorced in 1916. After an unsuccessful custody fight for her son Cedric, Leginska became even more outspoken about inadequate opportunities for women, stating that self-sacrifice for family's sake is "over-rated" and that "it is impossible for a woman with a career to be unselfish". From her official American debut in New York's Aeolian Hall on 20 January 1913, Leginska's popularity in the U.S. was growing, aided by both the careful staging of her performances, with well-thought-out lighting and decor to focus on the performer, and her distinctive style of dressing (favoring menswear) eagerly copied by her young fans, as well as her diminutive size and her youthful appearance that not only made the musical youth more likely to relate to her, but often misled not only her audiences but even the reviewers who would express their astonishment that a person so "young" displayed such skill as hers (this going on all the way into Leginska's late thirties, as made evident in the Detroit News critic Robert Kelly's description of her perform at 37). In 1923, Leginska went to London to study orchestral conducting with Eugene Goossens. She also studied conducting with Robert Heger, conductor of the Bavarian State Opera in Munich, proceeding to conduct as guest conductor with major orchestras in Munich, Paris, London or Berlin, taking advantage of her earlier contacts established when she performed as a pianist, as well as agreeing to also perform in a concerto on the programs. Being a woman conductor also helped her attract attention, as a novelty. She conducted a performance of her orchestral suite Quatre sujets barbares. In 1925, she made her debut as a conductor in the United States with the New York Symphony Orchestra in Carnegie Hall, after which she appeared with the Boston People's Orchestra in the spring and then performing at the Hollywood Bowl in the summer of 1925. She had suffered nervous breakdowns in 1909, 1925 and 1926. In 1926 she announced a permanent retirement from performing as a pianist and focused on conducting, composing and teaching. Though her output as a composer was limited, she distinguished herself as an organizer, establishing the Boston Philharmonic Orchestra which she conducted (1926–27), heading the Boston Woman's Symphony Orchestra (1926-1930) with which she went on two extensive tours. She also directed the Boston English Opera Company, founded the National Women's Symphony Orchestra in New York in 1932 and served as director of the Chicago Women's Symphony Orchestra. In the late 1930s, when her conducting opportunities began to diminish as her novelty wore off, she left the U.S. again, to teach piano in London and Paris before settling in 1939 in Los Angeles. She opened a piano studio and was a well-respected teacher into the 1950s. In the meantime, in 1943, she founded the concert series New Ventures in Music, with Mary Holloway, mainly to promote her pupils. In 1957 she once again conducted - a Los Angeles performance of her first opera The Rose and the Ring, written in 1932. Ethel Leginska died in Los Angeles of a stroke on 26 February 1970, aged 83