I came across this in Slate's Human Nature colum today:
A birth dearth is forcing Singapore to promote sex. The birth rate there is 30 percent below what's needed to replace the population. One big reason: Economic pressure makes Singaporeans work so hard, they have no time or energy for sex. The government warns that if births don't increase, the country will need more immigrants. So, it's promoting sex therapy, loosening its control of porn, and offering benefits to working moms. Optimistic liberal view: Nature 1, Repression 0. Pessimistic liberal view: Capitalism 1, Nature 0. Cynical liberal view: Xenophobia 1, Prudery 0. (For Human Nature's take on birth control and "girth control," click here. For the shift from sex to cybersex, click here.)
Japan hasn't gone to the same lengths as Singapore...yet, but I think these reasons apply to Japan as wel. However, there are some big differences, for example, they haven't offered benefits to working moms. And I think the female workforce in Japan is underused and that will have to change in the future. I also think that they will eventually have to open the country to immigration cancelling out the "xenophobia factor." I also agree with the "pessimistic liberal view"-why does the coutnry have to grow economically-can't it just become more effeicient?