I think it depends on the appointment. If someone's going to be poking around (I mean, a nurse or doctor, not the person you're doing the deed with) down there, it's probably polite to not have sex just prior (so you're not still semen-y). If it's a regular ol' appointment and there' no anticipated exam or anything, I think it's fine.
SAH dissertating mama to my sweet little boy (2/2009) and his baby brother (7/2011)
If it is then I'm in trouble! I don't have the mw do vaginal exams though, so I'm sure it wouldn't matter to me. But if you do have vaginal exams done, I don't really know. I can't imagine it would really change anything, so personally, I'd do it whether I had an appointment or not, but I'm no expert.
Jennie, mama to Wyatt (3/25/09) and Emma (11/22/10)