The sole alternative role for women which had existed outside of marriage, to join a convent, was no longer available in Reformed Protestant areas, although some convents voluntarily participated in the Reformation. For example, following Catherine of Mecklenburg's choice to defy her Catholic husband and smuggle Lutheran books to Ursula of Munsterberg and other nuns, Ursula (in 1528) published 69 articles justifying their reasons to leave their convent. Although her writings reached Martin Luther, they were listed on the Index Librorum Prohibitorum from 1596 to 1900.