She led the Ballets de Monte Carlo with Lacotte from 1986 to 1988.
She danced as a guest for the Rambert Ballet, the Grands Ballets Canadiens and the New York City Ballet.
She has taught for the Paris Opera Ballet.
She was frequently partnered by Michael Denard.
Her most celebrated roles include Odette/Odile in Swan Lake and Giselle in Giselle.
The ballet film La Sylphide (1972) has been released twice on DVD/video and features Thesmar and Denard in the principal roles of the Sylph and the Scotsman, James.