Charles Ellicott Commentary Exodus 1:21

"And it came to pass, because the midwives feared God, that he made them households." — Exodus 1:21 (ASV)

He made them houses. —God rewarded those who had shown tenderness to young children, by giving them children of their own, who grew up, and became in their turn fathers and mothers of families. There is no indication that the “houses” spoken of were Hebrew ones.