There was no imperial letter issued to permit use of "In" title because nyoingo (a title of respect given to close female relatives of the Emperor or a woman of comparable standing) was abolished due to the Meiji restoration, but she was kindly treated as kokumo (mother of Emperor) accordingly.
明治維新による女院号廃止のため院号宣下は無かったが、国母として相応に厚遇された。