In addition the midrash collection Leviticus Rabbah (14.9) comments on Leviticus 12:2: “It [namely, the determination of the embryo’s sex] may be likened to two artists, each of whom executes the likeness of the other; thus it is always that the female is formed from [the seed of the] man and the male from [the seed of the] woman. This is indicated by what is written … (Leviticus 12:2 and Genesis 46:15).”