Ryota Mugiyama, Shin Okubo, Kota Toma, Shigeki Matsuda
SocArXiv 2026年4月8日
<p>Low fertility in East Asia has been partly attributed to family policies that target married couples and working parents while neglecting the unmarried and childless individuals, who account for fertility decline through decreased marriage prevalence. The close linkage between marriage and childbearing in this region, however, proposes an alternative possibility: never-married individuals form their intentions by reasoning prospectively about family policies in terms of the potential financial benefits and the uncertainty associated with future childbearing. Conducting factorial survey experiments of age 20–34 never-married childless individuals in Japan, we examine how changes in six family policy dimensions—childcare leave benefits, child allowance, university tuition, daycare availability, short-time work, and overwork restrictions—affect fertility and marriage intentions. The results show that more generous financial incentives and work-family policies significantly increase both fertility and marriage intentions. While the most generous alternatives generally produce meaningful effects, the effects of modest reforms are frequently insignificant, suggesting that incremental policy reforms may be insufficient to shift family formation intentions. These findings provide insights for policy design and scaling in East Asian societies characterized by a strong marriage-childbearing linkage and potentially in other post-industrial societies with persistently low fertility.</p>