Really, when a person is born, it is called pure heart period, which is congenital. At that time, there was no world dust pollution, so it was a person's initial and most primitive state. As for being in the mother's belly, it is in the process of life birth, and a real person has not yet been born, so it cannot be called the most primitive state of human beings.
Congenital qi is the first breath when a person is born, also known as the source of life.