According to the Oxford Dictionaries, impromptu as an adjective and an adverb means 'done without being planned or rehearsed'. As a noun, it means 'a short piece of music, especially a solo, that is a reminiscent of an improvisation'.
We chose the word 'impromptue' for its essence of spontaneity. Through our events, we aim to create a community that thrives based on the spontaneity of its members, the various guest panelists, and the women we portray.
The additional 'e' brings its edge to the word. In French, the 'e' feminizes the adjective. Voilà, we come full circle.