St Thomas Acquinas pioneered the use of “reductio ad absurdam” for theological arguement.
So .. if a conceptus .. the cell ball we all begin from from, is a baby, then yes abortion is murder.
This leads in directions that some may not like. About 1/3 of all conceptions end in a spontaneous abortion. If we follow St. Thomas, then we MUST prevent all of these.
In other words, we need to confine pregnant women to assure they do nothing to murder their incubus.