Help: Preventing Embarrassing Moments In Speeches/Presentations

HELP!!! what do you do when you're in the middle of an important speech or presentation and suddenly realize you're about to start going Pee while you speak and there's nothing you can do to prevent it? anybody had this happen to them or been there before? if so, how did you handle the pressure of the situation without ruining your Speech or Presentation? please share if you would.

Thanks

go to the potty before the speech