Hint: not everyone shares your notion that life beings at conception.
It's almost like not everyone is operating on the same principle as you. Wait a second! I actually already pointed that possibility out to you...
From my previous post:
Humankind is not a big hive mind. ANYONE basing their stance on abortion on a basis different from your own...is working from a principle at least slightly different from yours.
Really, once you acknowledge that the global human population is NOT 1 (i.e., just you), the answer to your question is simple and obvious.