Ummmmm...

Don't you ladies in the states have those "hygenic" seals on all togs/bathers, bikeshorts and other unmentionables. the "GOOD" brand bike shorts over here do. Plus the tri suit I bought from TE did too.

I have however seen in the changing rooms in the city a sign saying "wear your undies while trying on shorts please"

Also on the tag of my Pearl Izumis it read "wash before use"

So yeah. in the interest of your health I'd say wash. I do.