This poster from the second world war shows that even when faced with an enemy as ferocious as Hitler, it’s imperative to keep a clean whistle. I’m going to keep posting these retro sexual health warnings because I think they’re great fun, even if some of the language – particularly towards women – is a tad primitive. “Procurable women,” for heaven’s sake! Use terms like that nowadays outside the confines of certain misogynistic members clubs, and the only feeling in your privates will be that of a solid kick. And quite right, too.