China is taking the first step towards ending its one-child policy with the authorities in Shanghai encouraging thousands of couples to have a second baby.

For the first time in 30 years, officials in the country’s economic capital have urged eligible parents to plan for a second child. The move was prompted by the growing demographic imbalance in the city and fears that the younger generation will not be able to support the ageing population. The one-child system, where all pregnancies are monitored and sometimes terminated by order, was enforced to control a population that is the largest in the world at more than 1.3 billion.

“We advocate eligible couples to have two kids because it can help to reduce the proportion of the ageing people and alleviate a workforce shortage in the future,” said Xie Linli, the director of the Shanghai Population and Family Planning Commission.

The one couple, one child family-planning policy is less rigorous than its name suggests. Urban parents are permitted to have two children if the husband and wife were only children. In rural areas, couples are allowed a second child if their first is a girl.

“Shanghai’s over-60 population already exceeds three million, or 21.6 per cent of registered residents,” Zhang Meixin, a spokesman for the Shanghai commission, said. “That is already near the average figure of developed countries and is still rising quickly.”

By 2020 the proportion of elderly is expected to rise to 34 per cent of the city’s population.

The elderly population is rising at a similar rate across the rest of China, mainly in cities, with the working-age population expected to start shrinking in about 2015. The overall population will peak in 2030, with China becoming the first country to grow old before it grows rich and therefore able to support a nation of pensioners.

The US Centre for Strategic and International Studies warned in April that by 2050, China would have more than 438 million people over 60, with more than 100 million aged 80 or over. The country will have only 1.6 working-age adults to support every person aged 60 or above, compared with 7.7 in 1975.

Most newly married couples registered in Shanghai were only children and are eligible to have two children, but many do not take up the privilege. The number of such couples has risen to 7,300 last year from 4,300 in 2005.

One couple in Beijing with a two-year-old son, who are entitled to a second child, said that they preferred to forgo the privilege. “It costs more than 35,000 yuan (£3,500) a year just to leave our baby in a kindergarten. Why spend this amount of money on a second?” one of the parents said. Many young couples are willing to have one child to continue the family line, but they let the grandparents raise it so that they can go to bars and restaurants and go shopping and travelling without being restricted by the responsibilities of children.

In Shanghai, where the rise in incomes is among the fastest in the country, young couples want to enjoy a level of prosperity unknown for more than a century.

An online opinion poll about the change in policy, by the leading portal Sohu.com, showed 374 respondents supported the policy because it would slow the ageing population and 514 were opposed, arguing that there were already too many people in China.

One chat room commentator said: “This should have been done long ago otherwise, in a few years, a child will have no uncles, no aunts. These titles will be completely forgotten.”

Another said: “These days who dares to have a second baby? The cost of living and education are so high. Best not to have one at all.”

One person remembered the policies of the 1950s and 1960s when Chairman Mao appealed for large families. “Our parents were poor and they had five or six children. Now we are better off, but having even one baby is difficult. In the future we may not be willing even to have one and it will be like the West with a falling population. Terrible!”

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