Then you will defile your idols overlaid with silver and your images covered with gold; you will throw them away like a menstrual cloth and say to them, “Away with you!” Isaiah 30:22 [NIV]
According to Old Testament law, a woman was considered ceremonially unclean during her period, and anyone who touched her was also unclean until evening that day . Menstrual cloths were, naturally, also unclean, and women threw them away.
When God’s people return to him, they will throw away their idols, much like abandoned menstrual cloths. Their idols will be as repugnant to them as soiled menstrual rags. Everything about these idols and everyone associated with them is unacceptable to the Lord. God wants a pure and holy people to walk with him.
(General Editor Jean E. Syswerda, NIV Women of Faith Study Bible, Zondervan Publishing House, Grand Rapids, Mischigan, 2001, pg 1155)