China's One-Child Policy is the most effective programme of population control the world has ever seen. But what are the long-term implications, asks Clifford Coonan in Beijing

Even in a country of 1.3 billion people, life can be lonely. Just ask some of the 80 million only children born in China since the One-Child Policy was introduced in 1979 to try to stop the country's massive population growing out of control.

To many older Chinese, 23-year-old Zhu Kai is typical of her generation - spoilt, too reliant on her parents and unsociable because she grew up without siblings. Of course, the graduate student from Jiangsu province resents this view. "There is a popular opinion that single children have grown up in comfort, brought up to be delicate and spoilt. But I think we miss having a bigger family, we miss having an elder brother or sister to take care of us. We're lonely," says Zhu.

A recent survey of 7,000 Chinese youngsters showed that 60 per cent felt miserable during their childhood, the products of the "4-2-1 syndrome", where four grandparents and two parents all focus their attention on one child.

"I still remember feeling lonely as a kid. My parents were very busy with work. After class, I went home by myself, and the house was always empty," says Wan Bo (26), who works in a cosmetics company in Beijing. "I'm very close to my cousins. I think that's because they replace siblings in my family, and they are as lonely as me. I always thought it would be great to have a brother," she says.

The One-Child Policy is the biggest, and certainly the most effective, programme of population control the world has ever seen. Fearful that the ever-rising birth rate would put too much strain on already stretched resources, the government made birth control mandatory. And it has successfully slowed population growth to around 10 million people a year - China's population would be 1.6 billion otherwise, the government says.

The terms of the One-Child Policy are strict, limiting people in urban areas to one child, and in rural China to two children, provided the first is a girl. As in many developing countries, rural Chinese prize their sons because they believe they are better able to provide for the family, work the land, support their parents and carry on the family name - appealing factors in a country with little in the way of a social security blanket.

In most Western countries, more girls are born than boys. But in China, the national census of 2000 revealed that 117 boys are born alive for every 100 girls - the result of sex-selective abortion. The government offers cash incentives to stop farming families aborting baby girls. The "Care for Girls" plan exempts hundreds of thousands of girls from school fees, and gives tax breaks and other privileges to the families. The programme hopes to reduce the gender imbalance to a natural average of about 105.

Gender scanning of the foetus is illegal in China but a large black market flourishes, with a scan typically priced at 50 yuan, around €5, if the child is a boy - and 30 yuan if it's a girl. Experts estimate up to half a million children are abandoned to orphanages each year - 95 per cent of them healthy girls.

There are nearly 13 million more boys than girls under the age of nine and there are forecasts that by 2020, China may have 40 million bachelors, or "bare branches" as they are called in Chinese, looking for a wife. There is already a problem with a rise in the trafficking of women, as well as the sale of women as wives in the countryside, and a much-feared resurgence in female infanticide.

In rural China, the overwhelming number of children you see are boys, and local government officials have plastered the walls of some villages with slogans saying: "Daughters are as good as sons!".

The skewed gender ratio is a relatively recent phenomenon - in 1982, the birth gender ratio was 108 boys for every 100 girls. In the cities, where job prospects for women are often as good if not better than for men, the ratio is more normal.

In farming families, the bias toward boys means many parents decide to abort if the unborn child is found to be a girl.But China's family planning ministry insists that the One-Child Policy is not to blame and points to South Korea, where 116 boys are born to 100 girls but where there is no child restriction.

Parents who comply with the One-Child Policy receive state support and get free healthcare. There are tough penalties for those who commit the crime of having a second child, known as a "stolen birth" in Chinese, including fines of up to five times a family's annual income and even forced sterilisation. Their taxes are raised and they no longer receive free health care.

But as China's economy booms, some of the new rich reckon there are sound economic reasons for paying the fine, and more and more people want the policy to end. "I have three brothers. We work together and nothing is too difficult. But I just have one son. He can do no wrong in his mother's and his grandparents' eyes. He gets anything he wants. But he doesn't study hard and he is very dependent on his mother," says Shi Gengsheng (36), who runs his own business in Zhejiang province. "So who can I pass my business on to? I have to have a second child. Even if the fine reaches a million yuan, I still want to have a second child," says Shi.

Wang Liwei (24) from Heilongjiang province in the north, came to Beijing to sell computers. He is working hard to make ends meet, even though he is one of the "spoilt" generation. He feels extra pressure to perform, as the only son.

"When I was little, I was kind of spoilt. As an only son in the family, I was loved by everyone. But after my dad died, I grew up overnight. I realise my responsibilities as an only son and have started working in Beijing," says Wang. "The only person I'm worried about is my mother. I think I will keep trying to build up my career in Beijing for a few years. Once I succeed to some extent, I'll get my mother here to live with me," he says.

Chen Fang (48), a primary-school teacher in Jinhua, in Zhejiang province, is one of five sisters. She has one daughter, aged 22, and thinks the One-Child Policy has served China well, particularly having lived through an era of shortages in the 1960s and 1970s. "Parents can support the children better and spend more on their education. Generally speaking, an only child can be more successful than one with siblings," says Chen. "As a teacher in a primary school, I notice that some little children are a bit self-centred. But with good education, they generally learn how to get along with others."

Looking ahead, China is facing into a major pensions crisis, which will ask questions of the One-Child Policy. Three-quarters of Chinese workers don't have pension plans, which means 70 per cent of retired people will have to be looked after by their families - their small families.

Life expectancy is on the rise - 70 years nationwide, nearly 80 years in Beijing. The number of people aged 80 and over will climb from eight million today to about 50 million by 2040. The number of people 100 years or older will rise to a quarter of a million by 2030, according to UN figures.

"My boyfriend and I often talk about how, after marriage, we will need to take care of four old people. Both of us are so busy trying to make money," says Wan Bo.

With all these challenges in mind, the government has tried to make allowances for future population needs and allowed single children who marry to have two children. Also in some areas, the government has allowed that when a divorced couple remarry, he or can have a second child.

"It's interesting that me and most of my friends who are only children, want to have two children in future," says Zhu."What would be ideal is a boy and a girl."