And when the Lord saw that Leah was hated, that is, that she was loved less than Rachel, he opened her womb and thus prepared her for bearing children, which are His blessing. But Rachel was barren, also by God's dispensation.
Related Commentaries of Genesis 29:31
Genesis 29:31
31 And when the LORD saw that Leah was hated, he opened her womb: but Rachel was barren.