The Birthworld was a planet located in the space of the galaxy's Delta Quadrant, named as such as the homeworld of the Vostigye civilization. After the Catastrophe, the Vostigye were forced to leave the Birthworld due to geographic upheaval caused by a white dwarf's effects. Following their departure, the Vostigye built self-sustaining biospheres in orbit of the Birthworld. (VOY - Myriad Universes novel: Places of Exile)