Despite the scarcity of representations of medieval Dominican nuns and mulieres religiosae, these images offer valuable information about the origins and development of the cult of certain female Dominican saints, the devotions and spiritual concerns of their patrons and main promoters, and the role played by the female branch of the Order of Friars Preachers in its reform throughout the 15th century. The present paper examines the iconography of three Dominican holy women: saint Catherine of Siena, saint Margaret of Hungary, and Blessed Helen of Vezsprém. New possible interpretations and lines of research will be suggested through the study of the spiritual virilization of these holy women who ended up assuming masculine virtues and bearing manly hearts.