Maybe Sheela has nothing to do with sex. We know caves are/were considered sacred. Many begin with a vulva shaped entry. Did the pagans carve the Sheela's to help them remember who they were and pretend to enter a sacred cave as they entered the church?

In the book "In The Dark Places of Wisdom" Peter Kingsley talks about ancient Greece and the Prophet/Healer Parmenides who used caves to dream and prophesy in order to heal people/society. The pitch blackness of the cave, the silence etc. created a void between reality and nonreality. He would slip into a trance which they called incubation and for days would travel in other realms to help his people.

That satans groin site, that fourwinds supplied, with exhibitionist figures proves that practically anything is possible in regard to the christians taking pagan beliefs and twisting them to suit thier purposes.... some holy, some evil.