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The Pon Farr is a stage in the Vulcan mating cycle that occurs once every seven years. It is a biological mating urge that can cause even the most stoic and reliable of Vulcans to become violent and irrational. If the urges of Pon Farr are not alleviated, the Vulcan undergoing it can die.

Until the events of Enterprise, it was canon that only Vulcan males undergo Pon Farr.