Being: The quality or state of having existence.” One might note that a positive pregnancy test results from the existence of some being.

Human: A rational corporeal being. Thus, a bipedal primate belonging to the genus Homo, especially Homo sapiens (rational man).

Is a human being a person? What is a person?

Person: An individual substance of a rational nature.

Yes, that substance causing the positive pregnancy test is a human being and therefore a person.