Christians and Jews have always valued the life of the unborn (remember Exodus 1-2?). Here is the Early Church Father Tertullian on how Christians in the early church viewed abortion.
"But in regard to child murder, as it does not matter whether it is committed for a sacred object, or merely at one’s own self-impulse - although there is a great difference, as we have said, between parricide and homicide - I shall turn to the people generally.
"How many, think you, of those crowding around and gaping for Christian blood, - how many even of your rulers, notable for their justice to you and for their severe measures against us, may I charge in their own consciences with the sin of putting their offspring to death? As to any difference in the kind of murder, it is certainly the more cruel way to kill by drowning, or by exposure to cold and hunger and dogs. A maturer age has always preferred death by the sword.
"In our case [i.e., for Christians], murder being once for all forbidden, we may not destroy even the foetus in the womb, while as yet the human being derives blood from other parts of the body for its sustenance. To hinder a birth is merely a speedier man-killing; nor does it matter whether you take away a life that is born, or destroy one that is coming to the birth. That is a man which is going to be one; you have the fruit already in its seed."