Captain Robert April wrote:
The race would probably go extinct if the females only became fertile only once every seven years, so it's much more likely that the pon farr mating drive is the only time they have to mate. Otherwise, they can (and almost certain do) mate any time they damn well want to.
That is not necessarily true. You are assuming that they only have a maybe 20 year window of fertility. I say it's much longer than that, allowing for 6- maybe 10 possible offspring. If each Vulcan woman theoretically has four healthy children who grow up the race is not extinct.