Mathematics was considered "not for women"

At the beginning of the 20th century, when women were legally "allowed" to study at German universities, it was customary, with very few exceptions, for a professor not to begin his lectures if he detected the presence of a woman in the classroom. It was a perverse form of discrimination, since most of them ended up leaving the classroom.

– https://www.enriquegracian.com/emmy-noeteher/

Translation from Spanish courtesy of DeepL (deepl.com).