This argument is largely based on the debate between Wisniewski and Block.

1. A zygote is to a fetus, what a fetus is to a baby, what a baby is to a child, what a child is to a teen, what a teen is to an adult, what an adult is to an elderly person. It is all the same human being throughout its life.

2. A woman that voluntarily brings a child into existence (whether intentional or not) has a positive obligation to see the pregnancy through until the child can survive outside the womb and someone else will take care of it (if she doesn't want it). It does not matter that the woman owns her own body because she was the one that brought the child involuntarily into a situation where it cannot survive without her. The child had no choice in the matter. Obviously, this doesn't apply to a woman who was raped.

3. It is similar to the following scenario. Imagine you bring an unconscious person onto your boat and set sail for 9 months. Do you have an obligation to feed them? Should it be legal for you to throw them off your boat at any time because you own the boat?