Pope St. Siricius said that God the Father reserved the womb of the Blessed Mother solely for his only-begotten Son.
St. Ambrose and St. Thomas Aquinas assigned a spiritual meaning to Ezekiel 44:2: “This gate is to remain closed; it is not to be opened for anyone to enter by it; since the Lord, the God of Israel, has entered by it, it shall remain closed.” Mary is the gate, and Jesus was the only one to enter it.
This was to emphasize that Jesus Christ was uniquely the Word Incarnate/Son of God.
Catholics refer to the Blessed Virgin as "Daughter of the Father, Mother of the Son and Permanent Bride of the Holy Spirit." If Mary is the "permanent Bride of the Holy Spirit," it doesn't seem likely that she would also have been a bride in the merely carnal sense.
Ok, I can understand that reasoning. Thank you for your response.