The Immaculate Conception was not a new revelation.

The Catholic Church teaches that revelation concluded with the death of the last Apostle.

The dogma arose from the Tradition of the Church, which consistently held that the Theotokos was at the time of Our Savior's birth free of sin, which was and remains reflected in the hymns and prayers of the entire Church, even of our separated brothers in the east.

On this matter the Church has consistently held that women cannot receive ordination, and it has always, everywhere, and without exception held attempts to ordain women as null and void and treated the recipients as non-clerics.

In the case of the Immaculate Conception the teaching arose in the ordinary magisterium infallibly and was made dogmatic in 1854. In the case of ordination the teaching arose in the ordinary magisterium infallibly and may well become a dogmatic pronouncement if the unwillingness to accept it continues to be an issue.