There was some occasion that the female Emperor was chosen when there was an issue to decide who to succeed to the throne, there were Emperor Suiko and Emperor Kogyoku who succeeded to the throne until there was appropriate male successor was found. (There were many theories of the reason why the female Emperors were chosen, some people are against the theory of not accepting the temporally Imperial succession until there was someone appropriate to become Emperor before the government of Ritsuryo codes system.)
皇位継承者の決定が難航したときは、女性天皇が選ばれることもあり、推古天皇、皇極天皇が即位して、他に適当な男子の皇位承継者が現れるまで皇位についた（女帝が選ばれた理由には諸説あり、律令制以前の中継ぎ説を認めないなどの異説が多く存在する）。