Emmy Noether was the first woman in Germany to obtain habilitation in 1919. But I remember to have heard in the debate concerning the situation of women in academic mathematics that took place on the occasion of the International Congress of Mathematicians 2006 in Madrid (mentioned in this report from the AWM), that, in fact, she has been one of the very few female mathematicians at Göttingen University to get habilitation for many years. Another one was Helene Braun (who, by the way, doesn't appear in the Wikipedia list of University of Göttingen people): according to what she explained in her book Eine Frau und die Mathematik 1933–1940: Der Beginn einer wissenschaftlichen Laufbahn, she achieved habilitation in Göttingen at the end of 1940 (or maybe at the beginning of 1941: I can only read an excerpt of the book).
I'm not completely sure if they really were the only two famale mathematicians at Göttingen who were able to obtain habilitation during these years, but I remember to have heard that there were no habilitations of female mathematicians at Göttingen for many years.
Maybe this was mentioned in the film Women and mathematics across cultures, which has been projected before the debate, but I'm not completely sure about that.
Does anyone have some details about this?