Kao-Tsung also had difficulties with his health and would be forced to repair to his inner chambers, where Wu would act as his chief advisor, issuing orders on matters large and small.
新唐書形容他每一病倒，則「政歸房帷，天子拱手矣」，後來乾脆就「殿中垂簾」，武后與之並稱「二聖」，生殺賞罰惟后命是從；到了晚年，高宗身體更壞，就「天下事一付后」了。