Since then, Shanghai has established about 400 kindergartens, mostly in suburban areas with migrant populations.

"Children born in 2008 will enter the kindergartens soon. The city is planning to set up more kindergartens in the city to meet the increasing demand," said Yin Houqing, deputy director of Shanghai Education Commission.

According to the commission, about 400,000 children in the city are now in kindergartens, and the number is expected to exceed 500,000 in 2013.

The city has also encouraged more approved private kindergartens and day-care centers to open.

In Beijing, about 600 kindergartens will be constructed and renovated by 2020.

"In the long term, authorities should encourage women to give birth and solve the potential problems caused by an aging society. But they should also take farsighted measures to cope with the changing population size," Zhou said, adding that the current baby boom is expected to last until 2015.