Biological fact is that life starts at the point of conception. That is when the determination of sex and characteristics are put in place. That is when a new human being is formed. That is when the DNA from mother and father are combined. This life will never develop into any other form of life but human being. From the point of conception human being evolves, develops and grows through different stages till the end of life.
All human beings, including unborn, are entitled to same constitutional rights.
Do we have a right to take a life of unborn, terminally ill or an inmate in a death row? Is taking a life always painless and free of torture?
Congressional filings of "fetal heart beat bills" for unborn and "ending of life bills" for terminally ill have been introduced and proposed. There are places where a coherent and terminally ill adult can approve and request medication for ending of life. An incoherent and unconscious adult in life support or an unborn cannot approve or request for an abortion or ending of life.
The point of beginning of life should not be an issue. The issue should be when, why and how to end any life and falls in the categories of law, morality, religion, economy, guardianship and health care.
Some gifts can be returned, but a gift of life should not be one of them.