There is such a concept as a soul. Some people believe that until the soul is attached to the body - that body is not a living human being. So you can see all the parts on MRI scan, but it is impossible to see if there is a soul already present. That it why some people don't consider fetuses a human being. And many people think that the soul is attached to the body at the moment of birth.
So you can talk about unborn babies all you want. Just your opinion, not a fact. The same way I can call a cow "an unmade steak". Same logic.