Show me a formal Protestant doctrinal statement that rejects the Council of Ephesus or the Theotokos which doesnt mean Mother of God it means bearer of God or a source that shows that there is substantial rejection among protestant doctrine and we can change it Until then Westminster Confession  affirms the theology of the theotokos if not explicitly the term that will cover Reformed and Presbyterian Christianity London Baptist Confession   also does that covers the Baptists Methodist Articles of Religion Article II also does Covering Methodists and associated groups like the Nazarene and the Solid Declaration of the Formula VIII also does Covering the Lutherans All thats left is the Arminians which dont typically have a formal creed statment and I think that the Evangelical Free Church the Evangelical Covenant Church and the Assemblies of God Church are fair representatives and all of them affirm the hypostatic union of the divine son to a human nature and the birth of the divine son with a human nature to Mary which is the theological underpinnings of the Theotokos That covers just about all of the formal Protestant bodies