China will be short of 30 million brides within 15 years, according to an official report into the country’s burgeoning population. About one in every ten men aged between 20 and 45 - equivalent to almost the population of Canada - will be unable to find a wife, it has projected.

The findings, from the State Population and Family Planning Commission, outline bleak prospects not only for bachelors. The report says that the inevitable gender imbalance could result in social instability - a threat that the ruling Communist Party regards as the greatest risk to its grip on power.

It is nearly three decades since China’s rulers implemented a strict "one-couple, one-child" family planning policy. It replaced Chairman Mao’s focus on a high birth rate, which had been intended to ensure that China could fend off enemies with human-wave warfare. The unintended consequences of this draconian birth control have become increasingly pronounced.

China’s population is forecast to peak at 1.5 billion in 2033. That growth, coupled with consequent demographic imbalances, will threaten social stability, the economy, the environment and jobs. By 2020, the report says, the number of men of marriageable age will outnumber women by
30 million. "The resulting confusion in the social order will become a serious hidden problem influencing social stability."

One effect of China’s strict population control has been a jump in gender selection of babies. Traditional preferences for a son mean that more and more women abort their baby if an early-term ultrasound examination shows it is a girl. Officials deny that the gender imbalance is a result of the family planning policy. It is illegal for doctors to tell parents the results of an ultrasound test without a medical reason, though many do so. As a result, abortions of female foetuses are widespread, especially in rural areas, as parents try to ensure that the one child they are allowed is a boy.

China’s gender ratio for newborn babies in 2005 was 118 boys to 100 girls, an increase from 110 to 100 in 2000. In some regions, such as the southern provinces of Guangdong and Hainan, the sex ratio has ballooned to 130 boys to 100 girls. That compares with an average for industrialised countries of between 104 and 107 boys for every 100 girls.

Tradition favours boys over girls because men are seen as the main family breadwinner and in China only a son can carry on the family line. Daughters are expected to leave the home and marry "outside", becoming members of their husband’s family. Anxious government officials have started a countryside campaign, painting enormous slogans on the walls of village houses, exhorting parents to value their daughters. "Having a daughter is as good as having a son."

The population report said: "We need to develop a ’movement to embrace girls’. . . and effectively contain the trend towards greater gender imbalances."

Chinese officials have given no clues as to how they plan to find wives for the battalions of bachelors now growing up in Chinese schools. Kidnapping of baby girls is becoming increasingly common, as families seek a future bride for their only sons. Trade in women is also a problem in many rural areas where poor farmers are unable to attract a bride.

The government is not yet ready to loosen its birth control policies and demonstrates pride in its achievement of preventing 400 million births through its one-child policy. Instead, authorities are taking steps to curb the adoption of babies - almost all girls - by foreigners to ensure they grow up in China.

The number of people of working age - between 15 and 64 - will increase from 860 million in 2000 to 1.01 billion in 2016, according to the report. That is more than the total in all the world’s developed nations In the next 20 years, up to 300 million people will leave their farms and descend on towns and cities to live and work. The report said: "Our country is currently experiencing the largest human movement and migration in history."

China is having to cope with becoming the world’s first country to grow old before it grows rich. The number of people over 60 will jump from the current 143 million to 430 million by 2040.

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