Personhood and the time of ensoulment

Most of the decisions in Medical Ethic, especially in ethical considerations in beginning and end of life depend on our definition of embryo and his/her ethical status. There are various factors to recognize someone as he human species such as impregnation time, implantation in the uterus, evolution of nervous system and senses, the embryos movement in the uterus of the mother, birth and conscious. The time of transformation of a human being to a person is different in various points of views, in the beliefs of Abrahamic Religions; besides physical features humans had spiritual features and with citing on this matter his/her ethical status can be defined. In this point of view personalizing a human being will be defined with his/her ensoulment, but the spirit and the procedure of ensoulment is a spiritual matter. This does not mean to deny the effect and the relationship of this phenomenon or synchrony of it by some physical effects. So there is a chance that because of this close relationship of spirit and the body, one can be able to identify physical changes in the body, which by them one can be able to guess the time of ensoulment or be able to claim that for embryo to have a spirit, he needs a certain extent of physical evolution. In this regard it is possible to ask that although the Islamic juridical point of view about the ensoulment and to determine 120 day of pregnancy as the time of ensoulment is a practical view but can we consider the embryo ready for ensoulment after being improved physically and to consider him as a person and to take all of the ethical consequences in to effect?!