You say, "I indicated that the baby was you, because it was dependent upon your eating to feed itself."
But that's not true ten minutes before it's born. Seems like a pretty imperfect doctrine.
Next was, "Also, it grew inside your body so indeed it is your body."
So if you become infected by a virus, parasite or bacteria, that is YOU? Even though it could be actively killing you, and is capable of living without any assistance from you?
What about a tapeworm that was birthed inside your body? Is that your body? Your argument doesn't work.
I don't think you've really proved that a fetus is the body of its mother.