Abortion ends a defenseless and innocent life. The genetic information of the baby is different from both the father and the mother. The conception of the unique genetic information is the conception of the child, When the sperm meets the ovum. There is no other point in the development of human life where you can look at what is there and say the day before there was no life and the day after there was life.
Killing an innocent and defenseless life is impermissible.