Abstract: China is undergoing profound demographic transformation characterized by persistently low fertility and rapid population aging. In response, the central government has introduced a series of pro-natalist policies aimed at promoting long-term demographic balance, with increasing attention to the multidimensional determinants of household fertility decisions. Among these determinants, time has emerged as an increasingly scarce and consequential resource in the cost-utility calculus of childbearing, particularly under the contemporary context of prolonged working hours in dual-earner households. As labor market competition intensifies and long working hours become normalized, household time resources are further compressed, potentially reshaping couples' fertility intentions and long-term family planning strategies.

Current research on the fertility-inhibiting effects of overtime work often lacks a family perspective, neglecting the fact that fertility decisions are fundamentally household-level choices shaped by intra-household interactions and joint time allocation. This study advances the literature by shifting the unit of analysis from individuals to couples and examining how different patterns of household overtime work influence fertility intentions through intra-household time coordination mechanisms and external time substitution.

Drawing on data from the 2024 Sampling Survey on China's Population and Family Development, this study constructs a typology of household overtime work patterns based on both spouses' working-hour arrangements and employs Logistic regression models to examine the impact of household overtime work patterns on individual fertility intentions, with particular attention to gender heterogeneity. In addition, we further explore the coordination mechanisms of intra-household time resources, and estimate the effect of marketization level of childcare services as a form of external time substitute from a family perspective.

The results reveal three main findings. First, household overtime work exerts a significant fertility-inhibiting effect, but the magnitude varies by overtime work configuration. Second, gender differencesare pronounced. Women's fertility intentions are more sensitive to household overtime work arrangements, reflecting gender asymmetry in domestic labor responsibilities and time allocation. Third,marketization level of childcare services has only a limited mitigating effect. It only shows significant effects among single-overtime work households, yet is invalid in dual-overtime work households.

This study makes several contributions. Conceptually, it introduces a household-level analytical framework that integrates time allocation theory and gender role theory to explain how cumulative overtime work generates structural time scarcity within families. Methodologically, it operationalizes household overtime work patterns as interactive configurations rather than individual behaviors and explains the mechanism through which overtime work affects fertility decisions from the perspective of reallocation of domestic responsibilities and changes in time allocation between spouses within the family.

These findings suggest that excessive working hours undermine fertility intentions by generating cumulative time scarcity within families and intensifying gendered inequalities in domestic responsibilities. Policies aimed at promoting fertility should therefore move beyond financial subsidies or childcare expansion alone and pay greater attention to working-time regulation, labor market flexibility, and the protection of family time resources. By emphasizing the family dimension of overtime work, this study provides new evidence for understanding the time mechanism of low fertility in contemporary China and for designing more effective family-friendly and fertility-supportive labor market institutions.

Keywords: Overtime Work, Fertility Intention, Time Resources, Family Perspective

摘要： 当前关于超时工作影响生育意愿的研究多聚焦于个体层面，忽视了生育决策的家庭属性，难以解释超时工作对在婚男女生育意愿的差异化影响。本文基于2024年中国人口与家庭发展状况抽样调查数据，从家庭视角出发构建家庭超时工作模式，系统考察其对个体(再)生育意愿的影响机制。研究发现，家庭成员超时工作显著抑制个体(再)生育意愿，且呈现明显的性别不对称特征，女性对超时工作尤为敏感，其(再)生育意愿不仅因自身超时工作而下降，更因配偶超时工作导致的家务劳动责任转移而遭受“双重挤压”。机制分析表明，闲暇时间挤占与家务劳动责任转移是超时工作抑制个体(再)生育意愿的重要路径，市场化托育服务的替代作用有限，难以缓解夫妻双方都超时工作的生育抑制效应。本文为构建家庭友好、生育友好的劳动力市场环境提供了实证参考。

关键词: 超时工作, 生育意愿, 时间资源, 家庭视角