MORE OPEN POLICY NEEDED

According to Cai's research, the second-child policy will help balance China's demographic structure in the long run, as it will increase the working population.

"While the shift of the current policy is important, the authorities should track fertility rates so adjustment to the policy can be made accordingly," Cai added.

If the population policy is not reformed, the future population growth rate will probably be less than 4 percent by 2050, which will threaten the current trend of a fast-growing economy, said Lu Yang, co-author of the report.

China's central authorities, however, remain cautious, with the National Health and Family Planning Commission repeatedly saying that there was no timeline for further changes to the second-child policy.

But even if China further lifted controls on its birth rate, the fertility rate will not increase drastically, as China is on its way to an aging society, according to the report.

"It is true that the population policy will affect the fertility rate, but the decrease of birth rate is an irreversible trend, since the fertility desire of the people wanes," Lu said.