Pon Farr

Pon farr ( /ˌpɒn ˈfɑr/) is a phenomenon in the fictional Star Trek universe. It occurs in the canonical TV series and in fan fiction based upon the series. In Star Trek, pon farr is a psychophysical condition affecting Vulcans, in which Vulcan males and females go into heat every seven years, going into a blood fever, becoming violent, and finally dying if they do not mate with someone with whom they are empathically bonded or engage in the ritual battle known as kal-if-fee. The idea is based on the mating ritual of animals on earth, notably the ferret that also dies if it has not mated by the end of the season. Vulcans also mate outside of Pon Farr, and with species other than Vulcan. A common misconception associated with the series (and Spock in particular) is that Vulcans only have sex once every seven years. However, pon farr is not coincident with the sex lives of Vulcans, and they are able to have intercourse without the affliction, and thus more than once every seven years.