Err, probably not... http://www.chakoteya.net/StarTrek/25.htm (emphasis added) Oh, wait... unless you mean that something happened while Spock was under the spores' influence. Hmm, in that case it's possible they got more intimately involved than '60s TV was allowed to admit. However, Enterprise suggested that Vulcan-human hybridization would require some medical/genetic intervention (which is in keeping with what was claimed in Roddenberry's Inside Star Trek record album from the '70s). Not to mention that there is such a thing as birth control.
Oh, Christopher, you're being much too serious with my flip little post. You are correct, of course, but I was thinking of the "spores" influence and Capt. Kirk's little jab about having the gall to make love to that girl. He was probably thinking, damn you Spock, that's my job!
Which reflects how language has evolved since the '60s. At the time, and going back to the 19th century, "making love" had a broader meaning than it does today; it could be used as a euphemism for sex, but it referred more broadly to the overall process of courting and romancing someone -- even just flirting with or sweet-talking someone. (Cf. Danny Kaye's The Court Jester, for example.) You often hear characters in old TV shows and movies talk about "making love" even when any mention of sex was absolutely banned by the censors (for instance, in I Love Lucy, where they weren't even allowed to say the word "pregnant"). http://boards.straightdope.com/sdmb/archive/index.php/t-63110.html So Kirk's line wasn't meant to indicate that Spock had had sex with Leila -- there's no way NBC's censors would've allowed such an assertion to get on the air. It just meant that he was being generally romantic and affectionate toward her.