Those symbols on restroom doors are a fairly recent phenomena.
In the '50s and '60s they tended to have the actual words "Men" and "Women" on them (except in the Mad Magazine satire of advertising where it was "Mennen" and "Womennen"), at least here in the states (no doubt some places fancier than say, Sears, had them labeled "Gentlemen" and "Ladies" instead).
I assume that abroad they were in the local language as well.
The stick figure itself, I suspect, has been around as long as there have been humans to scratch them in the dirt with a twig or finger.
They were certainly known over a century ago when used as a plot device in one of Doyle's "Sherlock Holmes" stories.