When FUJIWARA no Michinaga became a person in paramount authority after the death of Michitaka and the downfall of his legitimate son FUJIWARA no Korechika, Teishi became a powerless empress due to the downfall of her family home, even if she was the mother of Imperial Prince Atsuyasu, the first prince of Ichijo.
道隆の死去とその嫡男藤原伊周の失脚により、藤原道長が最高権力者となると、定子は一条の第1皇子敦康親王の母でありながら、実家の没落により後ろ盾のない無力な皇后に転落してしまった。