Why so many atheists are pro-abortion

I would say from my own personal observation that most atheists are pro-abortion (i.e. pro-choice). If you have read my other posts on abortion, you would know that I am a pro-life atheist. This is because I see value in human life that runs deeper than the material it is composed of. Someone that is pro-abortion objectifies (in order to dehumanize) a young human life in order to make its destruction morally permissible in their eyes ("it's just a ball of cells, and so on). Atheists tend to be pro-abortion because they tend to be more objective, and this is good for some areas of thought (like science and economics), but bad in others (like the value of human life and morality). An atheist tends to be more objective than most people, and this is why they are unable to see the value of human life. Obviously not all atheists are objective to the point of not being able to value human life beyond the cells that compose its flesh and bones, but it seems that the majority are.