When Roe v Wade was decided ultrasound was, “in its infancy”.
It was hard to tell a, “blob of tissue” from a baby with a heartbeat.
In another way, people have known always and forever that there is a child inside a pregnant woman. In so many languages they call pregnancy being "with child." Thousands of years ago. How would they not know?
The Prophets of Israel and the Fathers (and Mothers) of the Church spoke of unborn prophets called by name, and sanctified children in the womb.
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