I see where you got confused. They're independent beings in the scientific sense, not in the idiot-on-the-street "Ohmigod, they need something from their mothers, that means they AREN'T REALLY HUMAN!" way.
"The zygote, the embryo, even the fetus" need nutrition and protection from the woman to sustain their lives . . . the same things the newborn and toddler need from her later on. (And by the way, chanting scientific words over and over doesn't make you sound smart, especially when everything you say about them is wrong.)