Ave Maria Meditations
This union of the Mother with the Son in the work of salvation is made manifest from the time of Christ’s virginal conception up to His death. It is shown first of all when Mary, arising in haste to go to visit Elizabeth, is greeted by her as blessed because of her belief in the promise of salvation and the precursor leaped with joy in the womb of his mother. This union is manifest also at the birth of Our Lord, who did not diminish His Mother’s virginal integrity but sanctified it.
Vatican Council II: Constitution on the Church, 57