Abstract
It is well known that not only the increase of both unmarried and the married late in life, but also the lowering of marital fertility is the cause of below-replacement fertility in Japan. This paper aims to examine the ways and processes that family factors affect this lowering of marital fertility.
At first, I specify the three main hypotheses described in previous studies : socioeconomic causation hypothesis, value and attitude causation hypothesis, and gender causation hypothesis. I examine the logical relation among these three hypotheses, and show the logical importance of preference changes in child numbers by using the Boolean approach.
Next, I show that neither the findings of previous empirical studies nor the results of the Japanese National Fertility Survey support the gender causation hypothesis. Rather, it is suggested that the lowering of marital fertility might be explained by the changes in people's preferences to control the numbers of children for the pursuit of their wellbeing.
Third, using the NFRJ98 data, I analyze the family role overload feeling among married women who have babies and infants. These analyses do not support the gender hypothesis. The sexual division of labor is apparent in this life stage, but their feeling of a family role overload is very low. It is suggested that because tasks are not shared between husbands and wives, but rather shared among social networks members including close relatives, the gender causation hypothesis is not supported. It seems more plausible that the lowering of marital fertility is induced by the pursuit of children's well-being along with the traditional sexual division of labor within the family, rather than the products of some new changes in the family.
