Some more liberal Protestant Christians, such as those who belong to the Church of England, view abortion as wrong due to humans terminating life being a contradiction to moral law, but as permissible in certain circumstances, such as where the continuation of the pregnancy threatens the life of the mother.The Catholic Church and its followers, however, believe that unique human life and potential begins when the woman's egg is fertilised by a male sperm, and therefore that deliberate abortion is a grave moral wrong, on the basis of natural law and the written word of God.