Spock experienced it only once AFAWK - until being reborn, at which time he again only apparently experienced it once despite supposedly maturing through several decades. Vorik experienced it once (VOY "Blood Fever"), perhaps because he had no mate yet. Tuvok experienced it, too, despite previous experience, but perhaps because he had no telepathic connection to the mate he already had. His still remains the only confirmed case of a repeat performance of pon farr...
Although not confirmed, can we make the assumption Sarek went through pon farr twice?