One of the many well known differences between the sexes (aside from the obvious) is the fact that while just about all guys won't hesitate to let one loose when the need arises, it's pretty much universal that the girls in our lives don't ever seem to fart or do anything that isn't "proper". For that matter, I don't believe it's restricted just to the ladies either. If you doubt me, well, I am not a hamster, when was the last time you saw or heard of a guy in a tuxedo drop a real stinker? or belch like he was impersonating a chainsaw? I think it's because these few guys have figured out the ladies' secret.
Recently while cruising YouTube I ran across a video that I think explains how its that they manage this. It involves an awesome level of self control and timing. Holding things back until they're in a setting where they can unleash all that pent up nastiness without fear of any of the rest of us finding out that they did so.