Sanctity of unborn human life
The doctrine that the unborn child is a human person from conception, made in the image of God, and that intentional abortion is therefore the taking of innocent human life. This is the position of the historic church from the Didache (1st century) through Augustine, the Catholic Magisterium, and most evangelical and Orthodox bodies. Some mainline Protestant denominations have softened or reversed this position. Look for "pro-life", "sanctity of life", or by contrast "reproductive rights", "reproductive justice", "right to choose" as signals.
This doctrine distinguishes traditions but is not a boundary of orthodoxy.