She was part of the Danish team that won silver medals at the 1962 World Women's Handball Championship in Romania.

Birksome was introduced to the game in 1944-45 when handball players from Copenhagen-based club Handelsstandens Gymnastikforening were practicing at the school.

The following season, they reached the final, but lost to East German club SC Leipzig.

[1][4] In 1963 she became the head coach of the Denmark women's national handball team together with Birgitte Wilbek.

Birkmose was a board member of Københavns Håndbold Forbund from 1957 to 1958 and was generally involved in the organisation between 1954 and 1962.