It's not a Biblical fact. The term is found NOWHERE in Scripture.
The term *mother of Jesus* is, however.
I'll stick with agreeing with the Holy Spirit in what He inspired in Scripture: *Mary, the mother of Jesus*.
That way, I KNOW I can't be wrong.
The Holy Spirit is clear in Scripture in calling Mary *the mother of Jesus*.
John 2:1 On the third day there was a wedding at Cana in Galilee, and the mother of Jesus was there.
John 2:3 When the wine ran out, the mother of Jesus said to him, They have no wine.
Acts 1:14 All these with one accord were devoting themselves to prayer, together with the women and Mary the mother of Jesus, and his brothers.
Deal with it.
In case your own interpretation of the Bible didn't inform you......JESUS IS GOD...therefore Mary is the mother....oh well if you ever took a course in logic you'd be able to fill in the rest.
Since Jesus is God, Mary is mother of God.