Anti-abortion activists are fond of saying “The only difference between a fetus and a baby is a trip down the birth canal.” This flippant phrase may make for catchy rhetoric, but it doesn’t belie the fact that indeed “location” makes all the difference in the world.
It’s actually quite simple. You cannot have two entities with equal rights occupying one body. One will automatically have veto power over the other - and thus they don’t have equal rights. In the case of a pregnant woman, giving a “right to life” to the potential person in the womb automatically cancels out the mother’s right to Life, Liberty, and the Pursuit of Happiness.
After birth, on the other hand, the potential person no longer occupies the same body as the mother, and thus, giving it full human rights causes no interference with another’s right to control her body. […] After birth its independence begs that it be protected as if it were equal to a fully-conscience human being. But before birth its lack of personhood and its threat to the women in which it resides makes abortion a completely logical and moral choice.
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Why Abortion Is Moral, a good explanation of why common ethical arguments against abortion are horseshit
To summarize, if (1) you think zygotes/embryos/fetuses are people and that their rights to gestate trump the self-ownership rights of their mothers, then (2) you must concede that NO ONE has absolute rights to dispose of his/her own body as s/he wishes. That is, if you agree with the first point, then you’d also have to agree that someone without kidneys should be allowed to surgically attach themselves to someone with kidneys in order to live.
But if you refuse to make this second step, then you’re stating that only pregnant women should be denied full control over their own bodies. Which means you are basically suggesting that pregnant women have no more rights than incubators or brood mares—hardly an acceptable moral or ethical position.
