"O Mary conceived without sin, pray for us who have recourse to Thee."
St. Catherine did what Mary told her. The medals were called the Medal of the Immaculate Conception. As soon as people started wearing the medals, miracles were happening. People started calling them the Miraculous Medal.
Miraculous Medal Prayer
O Mary, conceived without sin, pray for us who have recourse to thee.
The following is from Father Tommy Lane's homily on the Feast of the Immaculate Conception.
I know that very many of you wear the Miraculous Medal. You may not know that it really is the medal of the Immaculate Conception of Our Lady...
The entire homily can be read here.
SOURCES: http://www.ainglkiss.com | http://hicatholicmom.blogspot.com