Genesis 25:20-22

Young's Literal Translation

²⁰ and Isaac is a son of forty years in his taking Rebekah, daughter of Bethuel the Aramaean, from Padan-Aram, sister of Laban the Aramaean, to him for a wife.

²¹ And Isaac maketh entreaty to Jehovah before his wife, for she [is] barren: and Jehovah is entreated of him, and Rebekah his wife conceiveth,

²² and the children struggle together within her, and she saith, `If [it is] right -- why [am] I thus?' and she goeth to seek Jehovah.