As you may already know, Ovid MEDLINE and PubMed were not updated during the recent US Government Shutdown. Ovid MEDLINE has not been updated since 2 October.
Therefore, on 23 October a larger update than normal will be published in order to catch-up. If you have alerts set up with MEDLINE, you may receive more results than normal.
After 23 October, the updating procedure will return to normal.