You cannot be “you” without being a person.
You were once a fetus.
Therefore you, as a fetus, were also a person.
To state again, an essential property of what makes you “you” is the fact that you are a person. It doesn’t make any sense to say that you once were an inanimate object. If you are essentially a person, and you were once a fetus, it follows that you as a fetus were also a person.
Just as we recognize we could not become a bat without ceasing to be ourselves, we cannot become an impersonal thing without our existence ending. I cannot become, nor could I ever have been, a rock or a toaster oven. Yet when we reflect upon it, we recognize that we were in our mothers’ wombs. We cannot deny this without going against all of our intuitions about ourselves….
If the unborn was not the same being at all [biological] stages of change, the term “development” would not be appropriate. The biological terms themselves suggest a human being maintains the same identity over time. A fetus is to an infant as an infant is to a toddler. If a fetus develops into an infant and then to a toddler, this is one and the same being that goes through this development. Given the first premise, this would only be possible if the fetus is a person.
~ Timothy Jackson, The Federalist, April 18, 2017