<sarcasm>what? a catholic would NEVER use pagan symbolism and rituals to help convert pagans to christianity, they would only use the power of the LORD!</sarcasm>
Then what ancient christian ritual do you think Sheelanagigs are a part of?
In Ireland Ireland's Sheela na Gigs
Armagh Cathedral (Cof I) Co. Armagh.
This is a very ancient and historical city and has played it’s part in many historical sagas. It is reputed to be the resting place of Brian Boru and his son after the Battle of Clontarf.
In the Chapter House there is a fine collection of pagan Celtic carvings. A female figure here has been disproved as a sheela as has the other male figure with a metal arm.
and in the UK SheelaNaGig.org a guide to Sheela Na Gig carvings in the UK