My convictions concerning the sanctity of life from conception to death are not primarily ethical or political in nature. 

They are theological. 

They are rooted in the biblical idea of mankind being created imago Dei, in the image of God.

I recently read the following words by R. Kent Hughes which reminded me of this great and beautiful truth:

"So consider this:  Though you could travel a hundred times the speed of light, past countless yellow-orange stars, to the edge of the galaxy and swoop down to the fiery glow located a few hundred light-years below the plane of the Milky Way, though you could slow to examine the host of hot young stars luminous among the gas and dust, though you could observe, close-up, the protostars poised to burst forth from their dusty cocoons, though you could witness a star’s birth, in all your stellar journeys you would never see anything equal to the birth and wonder of a human being.  For a tiny baby girl or boy is the apex of God’s creation!  But the greatest wonder of all is that the child is created in the image of God, the Imago Dei.  The child once was not; now, as a created soul, he or she is eternal.  He or she will exist forever.  When the stars of the universe fade away, that soul shall live."

[R. Kent Hughes.  Genesis.  (Wheaton, IL:  Crossway Books, 2004), p.36-37.]