Abstract: Due to the positive correlation between population size and technological innovation, there exists a positive externality in fertility, which is intertemporal and inseparable across regions. Since the benefits of high fertility are reaped at the national level, the central government has the principal responsibilities to implement pronatalist policies. Policy design deviating this principle would distort the behaviors of local governments. In this context, a well-designed pronatalist policy should clearly define the responsibilities between the central and the local governments to achieve a mechanism with incentive compatibility at both the micro and macro level. The core of pronatalist policy is to resolve the conflicts between childbirth and female labor market participation and to prioritize those that both facilitate childbearing and improve women's competitiveness in the labor market. Personal income tax deduction is one of the policies that meets the above criteria. The top-level design should complete the policy framework to effectively include women of childbearing age and implement targeted policies based on the characteristics of different groups.

Keywords: Pronatalist Policy, Externalities, Central Government Responsibilities, Top-Level Design

摘要： 由于人口规模与技术创新之间存在正向关联，因而生育行为具有正外部性(外部收益)，且这种外部收益具有地区间不可分割性以及明显的跨期性。获得生育外部收益的最明确的主体是国家，因此，支持和鼓励生育主要是中央事权。生育支持政策的顶层设计要合理界定中央政府与地方政府之间的权责关系，在宏观和微观层面形成激励相容的政策机制；要抓住制约生育率提升的主要矛盾，从化解女性生育行为与劳动力市场行为之间的冲突这一关键环节入手，优先选择既能鼓励生育又能提高女性就业竞争力的政策工具，个人所得税抵扣就是一项具有多重优势的政策；要注重政策体系的完备性和差异性，既能实现对全体育龄女性的有效覆盖，又能根据群体的差异性特征实施针对性的政策。

关键词: 生育支持政策, 外部性, 中央事权, 顶层设计