Do it! And the sooner in the conversation/meeting, the better. When I was younger I found myself always being afraid (and by afraid I mean often terrified) of what Other People would think about me if they knew or even suspected that I had a stutter. The older I get the less I find that I care what people think. And to boot, about 98 percent of the people I tell about my stutter literally couldn't care less about it. The other two percent usually remark that they have a relative with a stutter or are genuinely curious about it. Zero percent of people have used it as a means to be cruel/vindictive/etc. Good luck! It's a scary thing putting yourself out there like that, but it gets easier.