Yvonne Jaspar was her pseudonym in the Belgian Resistance.
Born in a well-to-do Bessarabian Jewish family, Groisman attended the Jewish gymnasium in Chisinau (present-day Moldova), coming to Belgium with the intention to study at the University of Liège, in the Philosophy and Letters section.
However, she changed direction, studying to become a social worker.
She took part in hosting child refugees from the Spanish Civil War and in arranging secret passage through Belgium of volunteers for the International Brigades.Jospa's husband Herz Jospa was arrested in June 1943, detained in Fort Breendonk, then deported to Buchenwald concentration camp in May 1944.