וְכִֽעֲסַ֤תָּה צָֽרָתָהּ֙ גַּם־כַּ֔עַס בַּעֲב֖וּר הַרְּעִמָ֑הּ כִּֽי־סָגַ֥ר יְהוָ֖ה בְּעַ֥ד רַחְמָֽהּ׃
And her rival vexed her sore, to make her fret, because the LORD had shut up her womb.
Read kabbalistic (mystical) interpretation of I Samuel 1:6: and classical mystical sources.