After joining Transparency International EU as a Communications Trainee in October 2025, Marthe became a Communications Associate. Prior to this, she completed an internship at the Flemish Parliament in Brussels. Marthe holds a BSc and an MSc in Communication Sciences from KU Leuven, during which she took part in an Erasmus programme at Sciences Po Toulouse, as well as an MSc in European Studies from Maastricht University.