diff --git a/addons/event/models/event_mail.py b/addons/event/models/event_mail.py
index 8d5ea40fc1a..58fc24af9ed 100644
--- a/addons/event/models/event_mail.py
+++ b/addons/event/models/event_mail.py
@@ -169,7 +169,8 @@ You receive this email because you are:
         for scheduler in schedulers:
             try:
                 with self.env.cr.savepoint():
-                    scheduler.execute()
+                    # Prevent a mega prefetch of the registration ids of all the events of all the schedulers
+                    self.browse(scheduler.id).execute()
             except Exception as e:
                 _logger.exception(e)
                 self.invalidate_cache()