基于CFPS2010、2012、2014、2016、2018五期的数据，采用双重差分模型分别估计了“单独二孩”政策与“全面二孩”政策对二孩生育行为的影响，并进行了安慰剂检验。研究发现：首先，“单独二孩”政策没有对二孩生育产生显著影响，这一结果与学界“单独遇冷”达成了共识；其次，“全面二孩”政策使得非独目标家庭二孩的生育概率显著提高了2.5个百分点，但该影响较小，没有从根本上扭转生育率下降的趋势。最后，“二孩政策”对于不同受教育水平女性的影响是不同的，“全面二孩”政策会显著提高中等教育水平女性的二孩生育概率，但对初等教育水平和高等教育水平的女性则没有显著影响。政府可以通过发展婴幼儿看护托管市场、对生育二孩家庭提供住房、医疗、教育补贴等配套政策进一步提高二孩生育率，特别考虑制定政策激励低教育水平和高教育水平人群的生育。

Based on the data of CFPS in the year of 2010, 2012, 2014, 2016 and 2018, the difference-in-differences model was used to estimate the impact of the selective two-child policy and the universal two-child policy on the childbearing behavior of two children. The results found that the universal two-child policy did not have a significant impact on the birth of a second child, however, the universal two-child policy made the probability of having a second child in couples where either the husband or the wife is from a single-child family, but the effect is small. Finally, the impact of the two-child policy on women of different educational levels is different. The universal two-child policy will significantly increase the probability of having a second child for women with secondary education, but it has no significant impact on women with lower and higher education levels. The government can further increase the two-child fertility rate through the development of the infant and child care market, housing, medical care, education subsidies and other supporting policies for families with two children.