Abstract
This study examines the impact of China's regional pilot programmes, which aimed to reduce the sex ratio at birth (SRB) by prohibiting prenatal sex selection. These programmes, implemented in six provinces between 1996 and 2001, served as a precursor to the nationwide policy introduced in 2003. Using a staggered difference-in-differences approach and microdata from the 2010 Population Census, we estimate the causal effects of these pilot programmes on the SRB. The results indicate a significant decline in SRB for second and higher-order births but no meaningful change for first births, suggesting a relatively modest overall impact. The policy was more effective among populations with better economic conditions and higher maternal education and among non-agricultural hukou holders and migrants. This heterogeneity underscores the importance of socio-economic factors, gender-egalitarian attitudes, and strength of policy enforcement in determining the policy's success. These findings provide valuable insights into the potential effects of the 2003 nationwide policy.