I am over 50 and when I grew up it was (and as far as I am concerned still is) certainly an extremely offensive remark and did refer to female genitalia, as did the word "pr*t", which is now more commonly used as a reference to your backside and as used by the Americans.
Captain Black, London
* or this whole thing is a very dry joke, which is conceivable, but the level of idiocy involved is by no means unusual for BBC commenters, so I am running with Occam's Razor.**
** which is much less dangerous than scissors