She was the mother of the incarnate, 2d person of the Trinity. He existed as the pre-incarate 2d person of the Trinity, and she was not the mother of the pre-incarnate person. After all, He predated her.
But there is no denying she was the mother of the incarnate Son of God. So, when the question comes up, I always emphasize the incarnation to be absolutely clear.
No one has ever said that she wasn't the mother of Jesus.