Why Dinah Is Called the Daughter of Leah

"And Dinah the daughter of Leah went out" (Genesis 34:1). Rabbi Hiyya bar Abba said: A male is always ascribed to the woman, and a female to the man. Then why is this one ascribed to her mother? Because the essence of her conception was male. Rather, at the time when Leah had borne six, and Bilhah two, and Zilpah two — behold, ten — Leah had conceived a male. At that moment she prayed on behalf of Rachel, and within her womb it became female. Therefore she is ascribed to her mother: "And Dinah the daughter of Leah went out."