Young Japanese 'decline to fall in love'
11 January 2012 Last updated at 05:13 GMT
Japan's population is getting smaller so to try to boost the birth rate, payments have been introduced for parents and steps have been made to improve access to child care.
But a government survey has revealed a big problem: over a third of young men and more young women have no interest in sex.
The BBC's Roland Buerk reports from Tokyo.