Page "Lumen Gentium" Paragraph 31

Some bishops had advocated a dogma of Mary Mediatrix, Advocate and Co-Redemptrix.

However, the Constitution did not mention the controversial notion of Marian co-redemption and instead only included a specific section on the Blessed Virgin Mary.

In part, this was due to the rise of Ecumenism and the need to maintain positive relations with Protestants.