Previous studies have reported the highest fecundability (monthly probability of conception) in women aged 20 to their early 30s, and declining fecundability with age. To better understand the age pattern of fecundability in Japanese couples we use time to pregnancy (TTP) to estimate conception probabilities by age. A total of 6,752 women aged 20-44 years residing across Japan completed a questionnaire on TTP, number of months between discontinuing contraception and conception for the first child. The analytic sample was n=1,324 women who had discontinued contraception within 60 months before the survey to conceive their first child. Cox proportional hazard regression model was used to estimate fecundability ratios (FR) and 95% confidence intervals (CI) by couple's age. Compared with women aged 24-26 years, women aged 27 or older showed a significantly lower FR. Advanced age of men was also associated with decreased FR. Cumulative probability of conception at 12 months after discontinuing contraception was highest for women aged 24-26 years, i.e. 80% (95% CI: 75%, 84%), and it was lower for higher ages, e.g. 66% (95% CI: 61%, 71%) at ages 30-32 and 48% (95%CI: 39%, 55%) at ages 36-38. Age effects on fecundability were less pronounced for parous compared to nulliparous women, and nulliparous women tended to be older and more likely to seek fertility assistance. Thus it is not just age effects but other, as yet unclear, factors are also likely to be contributing to low fertility in Japan.

Educational attainment of second-generation immigrants is gaining attention in the migration studies in Japan with the rapid increase in the number of immigrants since the 1990s. This issue has been studied intensively in other developed countries, wherein the importance of social integration has been underscored, so far, in terms of theoretical frameworks such as the segmented assimilation theory, which focuses not only on the practical disadvantages experienced by the second generation in a school but also on the socio-structural factors such as the parents' social class and their mode of incorporation. However, few studies have revealed the educational attainment of the second generation of several ethnic groups based on the nation-wide data in Japan. On the contrary, most studies have been clinical and small-sample surveys to assess the second generation' s adaptation to the Japanese school system, not from the viewpoint of its relationship with the social structure, such as the social class of their parents, or their mode of incorporation, which are regarded as powerful determinants of the educational attainment of immigrant children according to the segmented assimilation theory. The present study focuses on the high school enrollment rate of second-generation immigrants depending on the mothers' nationality by using the micro-data of the Japanese population census. In particular, the study applies the segmented assimilation theory to reveal their intergenerational class mobility. The results revealed that children of foreign mothers show a lower enrollment rate in high school than those whose mothers are of Japanese origin. However, their low enrollment rate is not due to their mother' s low social class, but due to their immigrant status per se. To sum up, the segmented assimilation theory is not applicable to the Japanese experience, although the results also revealed that providing more multi-lingual information and more supplemental Japanese language classes are needed to minimize the disadvantages of having a foreign mother, because a longer duration of residency alone cannot compensate for the disadvantages.

Saburō Ōkita （1914-1993） has been known as the ‘government economist’ （an economist who works at a government agency）. He played an important role in formulating the Income Doubling Plan （1960）, which sought to double the real national income within a decade, and also reaffirmed the government’s responsibility for social welfare, vocational training, and education. This new trend in formulating economic plans was based on the recognition that the growth of the productive-age population would decrease. By translating Eli Ginzberg’s Human Resources: The Wealth of a Nation in 1961. Ōkita imported the American idea of human resources into Japan. This paper illustrates the historical development of debates on human resources by focusing on the role of Ōkita.