I haven't met any of his female friends?

So Ive been dating this guy for over 7 months now. We haven't pushed for formal titles but for about a few months now we have both made it clear that we are exclusively dating one another. Although hes a really friendly social guy (which I like) he is still respectful and attentive when we are out in public. Here's the thing: Ive met most if not all of his close guy friends but virtually none of his female friends he went out with so often in the beginning. Is it safe to ume he doesn't want to introduce me because hes probably dating or has dated some of them?