So to put it simply, abortion = "baby killing". Here's an interesting question for y'all: Was abortion legal in the U.S. when our dear Constitution was written?
Oh! I know the answer to this one! Yes, until the "time of quickening". The first laws against abortion didn't start appearing until the 1820s.
No. It was a crime at Common Law. Read Blackstone and Justice Wilson.
"Life is the immediate gift of God, a right inherent by nature in every individual; and it begins in contemplation of law as soon as an infant is able to stir in the mother’s womb. For if a woman is quick with child, and by a potion, or otherwise, killeth it in her womb ... this, though not murder, was by the ancient law homicide or manslaughter. But at present it is not looked upon in quite so atrocious a light, though it remains a very heinous misdemeanor ..." (Blackstone, Commentaries on the Laws of England)
"With consistency, beautiful and undeviating, human life from its commencement to its close, is protected by the common law. In the contemplation of law, life begins when the infant is first able to stir in the womb. By the law, life is protected not only from immediate destruction, but from every degree of actual violence, and in some cases, from every degree of danger." (Justice Wilson, US Supreme Court 1789-1798, signer of Declaration and Consitution)
http://www.lifeissues.net/writers/tay/tay_03foundingfather.html
Misdemeanor at that time did not have the same meaning it has today (i.e. something like a traffic offense or not meeting an Affirmative Action quota), but meant very serious sorts of crimes, which is why our Constitution gives power of impeachment for "high Crimes and Misdemeanors".
Abortion prior to Quickening at that time was unprosecutable because it was undetectable, and because common opinion held mistaken views concerning human development given the then rudimentary level of medical knowledge.