In one parallel universe, Previous Doctor|a version of the Doctor was pursued by the Time Lords. He commited suicide by jumping off a pylon in an attempt to avoid capture, and in the process regenerated into a female.
In this universe it was against the law of the Time Lords to regenerate into a different gender. (AUDIO: Exile)
The War Lords were rendered extinct by the Time lords.
If you'd like to talk about narrative problems with this story — like plot holes and things that seem to contradict other stories — please go to this episode's discontinuity discussion.