Hmm. In "Amok Time", there's no mention of sex, obviously enough. Only about finding a mate. No cycle is suggested, either; when this follows in "The Cloud Minders", there's still no suggestion that it is connected to sex. To keep the censors happy, it's all about mating in the sense of finding a mate.
To which purpose it's useful that at least the females seem to get horny during their once-in-seven-years moment, as per ENT "Bounty" (although to be exact, there's zero mention of "seven years" there, only of a "cycle of mating" of unknown length). Males just seem to get drunk. As the result, a connection is made, and sex supposedly can proceed. Although funnily enough, we see pon farr on screen three times (male pon farr in "Amok Time" and "Blood Fever", female in "Bounty"), and it never leads to sex (or death) in those instances. Nor in the couple of instances off camera but in dialogue.
Nowhere is it suggested that Vulcanoids would need to be in pon farr to get horny or drunk, though. It seems instead that Saavik has sex with Spock easily enough at a totally random stage of her life in ST3. And nobody refers to seven dry years between intercourse, ever. Pon farr is just a possible time to have some sex, in addition to the mate-finding thing, not an obligation to have it (only T'Pol ever claims it would be, or at least she explicitly uses "mate" as a verb there, but she's shown to be wrong about that), nor the only time during which it is allowed.
Whether the Vulcanoids have a "reproductive cycle" at all is unknown. If they have one, there's no evidence it would involve seven-year intervals; no siblings are defined as being separated by exact multiples of seven years, say. It's equally unknown whether Vulcanoids have a "sex cycle" or whether they instead are in constant heat like humans (who have insignificant variations associated with the one-month reproductive cycle). All we know of is the "mating cycle", and even there we don't know if the cycle survives the actual mate-finding or terminates there.
Timo Saloniemi