Hi purps, as aligot wrote above, the Immaculate Conception isn't to be confused with the virgin birth.
However on a slightly topic-related tangent, Islam taught the Immaculate Conception as doctrine well before Roman Catholicism did! (and the fact that Islam was present in southern Europe for a few centuries until it was driven out might suggest that Saint Bernadette may have actually heard of the phrase 'Immaculate Conception' after all )