Application of the Theory of Planned Behavior to couples' fertility decision-making in Inner Mongolia, China

China relaxed its family planning policy and adopted a universal two-child policy on January 1, 2016 to actively address the country’s aging trend. However, the policy has failed to have any significant effect on the fertility rate of many provinces. In light of the country having the highest sex ratio at birth in the world and the huge burden of the aging population, improving the fertility rate is an urgent priority in China. This...