Abortion is no more an issue to be left to "the individual, thier god and thier doctor" than any other form of infanticide. No one has the right to take the life of another innocent person.
Either all living humans are persons, from the point of conception to the instant of death, or you deny the understanding that all men are created equal.
Conception is the only logical point of "creation" because, it is at that point that a unique, individual organism can first be distinguished according to modern sciences. According to biology, a newly formed zygote fits the definition of a living organism, and according to genetics, that organism possesses unique human DNA, discernable from that of its parents.