Other than Shoshi who became Empress, Reizei had various wives such as FUJIWARA no Koretada (FUJIWARA no Motokata's first son)'s daughter, FUJIWARA no Kaishi, but there were no sons yet and the selection of a Crown Prince was of immediate concern.
冷泉には皇后となった昌子のほか、藤原伊尹（師輔の長男）の娘藤原懐子ら複数の妻がいたがまだ皇子がなく、皇太子の人選が急がれた。