I see... but you are really just buying into a perception in relation to taboos and about how private parts are 'dirty' (a work with many connotations). In actual FACT, there is nothing dirty about 'down there'! Right now (if you are reading this) you are sitting at a keyboard that contains way more bacteria that a toilet seat! So do you wash your hands every time you use a keyboard? No? Because keyboards are not 'dirty' in the same sense that 'down there' is?
The main thing is just to wash your hands several times a day -since you go to the loo several times a day it's as good a time as any to wash them. But it's just a social convention, nothing more!
I'm starting to suspect you are one of those snooty visiting Oxford students!
(Kidding)