China's little emperors, the adored only children born out of the one-child family planning policy, are set to disappear after a single generation.

Anxious about the burden of a greying population and a widening gender imbalance, family planning authorities are considering scrapping a policy that they fear could become a demographic timebomb.

The world's biggest population of 1.3 billion lives on only 7 per cent of the arable land on Earth and is already straining scarce land, water and energy resources. The number, however, is likely to fall from the middle of this century, prompting worries among about how to slow the decline.

Zhao Baige, Vice-Minister of the National Population and Family Planning Commission, spoke of the need to relax birth-control policies and said: “We want incrementally to have this change.”

She was careful not to refer specifically to the one-child policy, which has attracted widespread criticism internationally for its draconian implementation that has even included forced abortions and sterilisations.

China was serious about relaxing its family-planning rules, although Ms Zhao declined to give a timetable. “I cannot answer at what time or how, but this has become a big issue among decision-makers,” she said - a clear indication in China's opaque system that a policy change is on the cards.

The one-child policy was implemented in the 1970s in a belated attempt to limit a population running out of control after Mao Zedong exhorted his people in the 1950s and 1960s to have large families, saying that more people meant a stronger China. He also believed that China could overcome its enemy at the time, the United States, with a human wave in case of war.

Tough birth-control policies are credited with preventing about 300 million births in China and helping to push the country towards greater prosperity. That achievement has come at a cost. A traditional preference for boys - seen as the only way to carry on the family line and a necessity for the farming families that make up the majority of the population, has resulted in a widening gender imbalance.

Experts estimate that 119 boys are born in China for every 100 girls, compared with the normal average of 107 boys born for every 100 girls. With nearly a quarter of the total Chinese population expected to be 65 years or older by the middle of the century, the little emperors will have to bear the burden of supporting this rapidly ageing people lacking proper pensions.

Ways to avoid a new population spike while preventing such imbalances are under serious study. The Vice-Minister said that research teams must consider the strain of China's huge population on its limited resources as well as population attitudes and just how much of a social net the Government could afford to provide without the traditional reliance on large families to care for the aged.

Surveys show that 60 per cent of Chinese under the age of 30 want no more than two children, and only a very small number want more than three. The average number of children born to a woman in her lifetime has fallen to 1.8 in China today - from 5.8 in the 1970s, and below the replacement rate of 2.1.

The headache for family planners comes from a combination of the huge numbers and entrenched traditions. The population is set to grow to 1.5 billion people by 2033 with birthrates likely to soar over the next five years.

Already many people are ignoring the rules - particularly the 150 million or more migrant workers who travel from poor rural areas to work in the more affluent cities and who can more easily escape the eye of officials.

China began relaxing the one-child rules a decade or so ago. Farmers whose first child is a girl are allowed to try again for a boy, although many already ignore that. Couples in a second marriage may also have another child. Those who flout the policies face a stiff fine - often several multiples of their income - or, in the case of government officials, dismissal.

‘We’re so glad we had a daughter’

Song Xiaoshi and his wife are the doting parents of a three-year-old girl. Mr Song, a highly educated Beijing office worker, is thrilled that their one child is a daughter. “A girl has closer ties with her parents,” he said, “and in the city we don’t need sons to work in the fields. In fact, when a boy grows up and gets married he has to buy a flat and his parents must help him, so this brings more worries about money.”

Mr Song is one of a growing younger generation that appreciates the birth control policies. “I would have wanted another child, but the problem is that this brings a very heavy financial burden.” His wife stopped working when their daughter was born and the couple could be stretched if they had a second.

Mr Song regards the one-child policy as necessary, but added: “Having a child is very good for our marriage. It creates a bond. So, if it were possible, I might still want to have a second child.

“Still, it’s a difficult decision.”

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