Do cats having a baby seek refuge in other homes if they're abandoned by their owners?

Cats are much more independent and less social than dogs. It's true that abandoned cats might seek a new place to live if their owners don't provide food or abuse them.

Pregnant cats have an instinct to seek a calm and safe place to make a nest for their kittens. Newborn kittens are blind and helpless and the mother wants to find a place where the kittens are safe for several weeks. That's why you should provide several places for your pregnant cat, like cartons and boxes with soft blankets.

The instinct to find a safe nest is so strong in cats that sometimes they walk around and seek a new nest while the contractions have already started and the birth is imminent. Then they must give birth in the next best place they find. This might have happened in your case.

Another possibility is that there are children or other pets in the home of the cat and she felt that her kittens would be disturbed by them. She was not abandoned, but was looking for a calm place.