Arroyo was politically active while living in Spain, serving as vice president of a women's anti-fascist association and participating in several feminist organizations.

It was this, as well as her alleged ties with the Soviet Union, that made her and her husband targets of the Nationalist faction in the Spanish Civil War.

[5] Her father had to complain to the director of public instruction[3] and she was required to take a unique exam to prove her ability.

[1] While at Valladolid, Arroyo became interested in surgery, but she specialized in ophthalmology as she appreciated the delicacy and precision involved,[6] and she determined that it was more open to women.

[6] After graduating from Valladolid, Arroyo attended the University of Madrid for her doctorate while studying under Santiago de los Albitos.

For two years, beginning in 1906, the couple left Madrid for Galicia while Márquez held a position at the University of Santiago de Compostela.

[6][8] In addition to Spanish, Arroyo was able to speak English, French, and German, which was of great use to the associations that she was involved with, as she was able to represent them to other countries.

[3] The Mexican government welcomed Spanish exiles through the Casa de España sponsorship program, and they quickly integrated themselves within the community of Spanish intellectuals in exile, along with figures such as Ignacio Bolívar, José Gaos León Felipe, and Max Aub.

[6] She chose the Instituto Libre de Segunda Enseñanza as the recipient of her donation as it was the school that allowed her to begin her studies.

[6] Arroyo was the vice president of the National Committee of Anti-fascist Women,[9] and she worked to strengthen ties between the Soviet Union and Spain through the creation of a social exchange program on 30 January 1937.