It has to be a hoax. I truly hope so, anyway.
I just saw this posted in the Facebook group "1960's and 1970's Advertisements". From there I tracked it back to a post from last June in Anorak. The oldest post I found was on Flickr from 2008.
Does anyone have provenance on this? Claimed to be from a 1974 "rock magazine," it parodies a long-running campaign for Maidenform begun by the William Weintrob Advertising Agency in New York:
If you have any information about this, please comment below.