Copyranter just posted this cover from Playboy South Africa that turns a woman's lips sideways to mimic the "other" labia.
I was sure I had seen this visual trick before. Here's one from Y&R Mexico, via Advertolog, from 2004:
Not that it's any more imaginative, mind you. (It's also been done with a heavily-lidded eye.)
Cheap shock, and it's been done before. Yawn.
If you find any other examples of this concept, link them in the comments.
Update: Here's a poster for the Vagina Monologues, done by Saatchi & Saatchi New Zealand in 2002 (via Coloribus):
Update 2: Just found three more (spec?) from DGLY Shanghai, China, for Dior Addict High Shine Lipstick in 2009 (Via Ads of The World Forum):
|It's green! With teeth!|
How many times can you do the same freaking "vulva face" ad?