The short answer; I haven't tried. I decided at quite an early age that I wouldn't have sex just for the sake of having sex, meaning I'd wait until I was in a meaningful relationship. I'm still working on that one. It's not really for any particular reason. I'm not sure if I'll stick to that if I get an offer (and I've had one or two, though I prefer if my first partner is a sober one), but I'll probably not actively try. At least not yet. I could probably do something about it if I really wanted to (apart from being 5'8 and having a fairly slight frame, I don't think I suffer from any major "defects).
It's not something I'm proud of, but I'm not really ashamed either. I'd be more open about it if people didn't get that "oh, I'm sorry" look. In general, it seems other people are more concerned with my sex life than I am, which is both rather odd and disturbing.