Many moons ago I heard this phrase. Apparently, if one washes one’s upper torso while standing at a sink, one is taking a “whore bath”. I can understand the meaning.
Has anyone else heard this phrase? Any ideas as to it’s first usage?
I’ve heard it before, and it was explained that it’s the only type of bath for which a prostitute might have time between clients.
The first time I “heard” it I actually read it, in a novel. I forget the title and author, but it was about some people putting on a passion play in Texas somewhere. I took it for Texas slang, but of course I’m probably wrong.
Mike Myers uses it (the phrase, not the bath) in the first Austin Powers movie.
My understanding is that it is washing the undercarriage (and perhaps the underarms) with a washcloth at the sink- cleans the stinky parts without too much fuss.
Not the upper torso, exactly – at least according to this source (my quick Google search failed to turn up an authoritative etymology):
I use the phrase whore bath all the time 
I grew up in an era when Polish jokes were all the rage. There is probably a thread about the reasons for this somewhere in the SDMB archives.
Anyway, when growing up, this practice was always referred to as a “Polish Shower”.
My mother-in-law, a very proper lady, surprised me one day when she called this a “PTA bath.”
PTA = Pussy, Tits, Armpits.
My understanding of the term has always been that it was a dousing in perfume or cologne rather than anything to do with soap and water.
YMMV.
Bob
Please don’t use that acronym following a sentence such as that. It’s too easy to read as YUMMY.
Ick.
Dousing with perfume or cologne is known as a Puerto Rican shower where I’m from ( NJ ).
I’ve also heard it more delicately referred to as a “birdbath.”
If I didn’t know I wasn’t married - I’d have to wonder if you meant MY mom! She (very stiffly proper) said this one day too. Must be something taught in those Catholic schools…
We used to call Speed Stick and Drakkar Noir an Italian shower!
This was called a “spit bath” in my family, but I was raised in an Anabaptist sect, so certain types of ladies and language were not part of our vocabulary. Oh…how far I’ve come. Grin.
Perfume-dousing is called the “Spanish bath” in my country. This is funny, everybody thinks somebody else stinks. 
The whole perfume-or-cologne-instead-of-bathing trick is referred to around here (Maryland) as either a “Italian Shower”, or, more racially toned, “Boofer Bath”.
“Boofer” is a derogatory term for African-American.
Where I grew up, peeing into the wind was caled a Polish Shower.
As for the OP, I’ve heard/read the phrase so many times, I wonder if it isn’t from very long ago. Maybe as old as the word “whore” itself.
Polish shower defined as peeing into the wind!!?? Hysterical, and I’m a Warsaw Warrior.