Upon the stools - Literally, “two stones.” The word denotes a special seat, such as is represented on monuments of the 18th Dynasty, and is still used by Egyptian midwives.
Related Commentaries of Exodus 1:16
Exodus 1:16
16 And he said, When ye do the office of a midwife to the Hebrew women, and see them upon the stools; if it be a son, then ye shall kill him: but if it be a daughter, then she shall live.