Since the male Imperial Family was not born from the birth of Imperial Prince Akishino-no-miya Fumihito in 1965 through the birth of Imperial Prince Hisahito in 2006, males in the male line, who could succeed the Imperial Throne, is in short supply, and there is a possibility of the extinction of the Imperial line because heir to the Imperial Throne, as regulated in the Imperial House Act, no longer exists.
1965年の秋篠宮文仁親王の誕生から2006年の悠仁親王の誕生まで男性皇族が誕生していなかったため、皇位を継ぐべき男系男子が不足しており、皇室典範に定める皇位継承者が存在しなくなり、皇統が断絶する可能性が出てきた。