|China's one-child policy has made the preference for male children more pronounced [EPA]
In the three decades that China's one-child policy has been in place, the Chinese government claims it has prevented 400 million births.
Its implementation has been relaxed over the years with numerous exemptions now permitted, but its longer-term consequences are becoming increasingly apparent - particularly in the country's growing gender imbalance.
A report conducted by Chinese and Western scientists and published in the British Medical Journal last year found that in 2005 there were 32 million more males than females aged under 20 in China.
A byproduct of China's 30-year-old family planning policies, this gender imbalance is now manifested most clearly among those of marrying age.
The Chinese Academy of Social Science estimates that by 2020, 24 million Chinese men will be unable to find a wife.
"[The gender imbalance] means that one out of four men won't be able to find a wife," says Liu Dajun, a sociologist at Shandong University. "This will have a huge impact on our society."
Some believe that impact is already being felt as single Chinese men, referred to as 'bare branches' because they will not bear children, appear as an increasingly high risk group.
Lena Edlund, a professor of Labour Economics at Columbia University, says China's gender imbalance is partially to blame for an increase in violent and property related crimes.
"Unhappy, frustrated people are by themselves a problem for society since they are part of society. The problem gets magnified if those individuals act in anti-social ways. Men without partners and children are a risk group in this respect," she says.
"Moreover, increased competition for partners may make men undertake more risky behaviour in order to advance in the socio-economic pecking order."
'True love' guaranteed
|For many young urban Chinese marriage takes a back seat to career [EPA]
But as more men encounter difficulties in finding a wife, one traditional Chinese profession is enjoying a revival - matchmaking.
"True love has nothing to do with luck or fortune, true love is a science," says Yang Yue, who works for an online marriage agency called Zhenqing Zaixian (true love online).
"I have a 62 per cent success rate, when someone comes to me for help, he is virtually married."
Zhenqing Zaixian is one of the most exclusive matchmaking agencies in China. Registering with them costs $1,785 [12,188 yuan] and new members must provide a character reference and verification of their income.
In return, the agency promises professional coaching, carefully selected dates and relationship counselling from the first date to the wedding day.
Those who do not turn to professional matchmaking agencies often rely on more informal methods.
Parents looking to find a match for their son or daughter gather in parks across the country. Some even print posters advertising their child and include details like their income, level of education and a description of their character.
But, many young Chinese women are choosing to postpone marriage.
Chen Guangyu is an only child with a busy career. When her friends' parents died recently, she says it made her realise just how lonely life as an only child could potentially be. But that was not enough to make her consider getting married.
"Like me, many of my friends are single, without any foreseeable potential husband .... One day, we will be the only one left [from our families] in the world. It is a terrible thing, but also a good thing because you enjoy absolute freedom," she says.
"Sometimes, I just want to be single all life long to enjoy [my] freedom ...."
But some young women face more than just parental pressure to marry.
Joan Kaufman, an expert on Chinese population and gender issues at the Harvard Kennedy School, says a "bride market" is emerging in which young women are kidnapped and sold into forced marriages in areas where the shortfall in women is felt particularly strongly.
|China's 'bare branches' may make daughters more valuable [Donata Hardenberg]
Some Chinese hope that the current gender imbalance may impact mindsets in a society that traditionally holds male children in higher esteem than female children.
Chinese traditionally consider boys to be more valuable because while girls typically leave their parents to live with their husband's family, male children take responsibility for supporting their parents in old age. And in a country without a social security net this can be critical.
Chinese culture also traces lineage solely through males and not carrying on the family name is considered a sign of disrespect to ones ancestors.
The introduction of the one-child policy transformed this traditional preference for male children into something with even more serious consequences for female foetuses.
In the early years of the policy, many expectant parents turned to traditional Chinese medicine or sorcery in an attempt to detect the sex of their unborn child.
But once ultrasound tests and abortions became more readily available, these methods were widely used.
In response to the high rates of female foeticide, the Chinese government banned gender determination tests. But in private hospitals and illegal offices the tests are still widely offered.
"While the [one-child] policy interferes with what many would view as one of the most important and private decisions in life, the problems with respect to the sex ratio stems from the Chinese being hell bent on [having] at least one son, and having little qualms about sex selection," Edlund says.
"Many people harbour preferences for the sex of their offspring, mostly in favour of sons, but acceptance of sex selection varies across cultures. What the one-child policy has dragged into full day light is the preference for sons and an acceptance of sex choice."
Buying an heir
Unwanted female children who are not aborted are often abandoned.
"We see girls being aborted and abandoned on a massive scale," Edlund says.
"Which is worse is almost a philosophical question. The vast majority of abandoned girls are raised in China, only a trickle are adopted in the West. How these girls fare is an interesting question. Traditionally, girls have been picked up by families seeking help with household chores and even to provide grand-children - [they are] raised as a 'little daughter-in-laws'."
But many hope the social stigma surrounding being unmarried may begin to change this preference for male children.
Wei Xingzhu, a professor at Zhejiang Normal University, says: "It is better to have a daughter who works and lives in the city, than a son who has to stay single."
But the preference for sons has created another lucrative business - a trade in male children that often targets the sons of migrant workers.
Some are allegedly sold in Singapore, Malaysia and Vietnam, but most are bought by Chinese families who desperately want a male heir.
The parents of missing children claim their cases are often ignored and that the police do not do enough to find their sons.
Su is a farmer who bought a boy for about $513 [3,500 yuan].
"I have one daughter. Girls are just not as good as a boy. It doesn't matter how much money you have, if you don't have a son, you are not as good as someone who has one."
|In 2009, 180 million Chinese were over 60 [Donata Hardenberg]
China's family planning policies have also impacted the country's generational balance.
In 2009, 15 per cent of the population, or 180 million Chinese, were over 60.
Family planning officials in Beijing estimate that by 2030, there will be 351 million Chinese over 60, or 23 per cent of the population.
And 30 per cent of the population will be over 60 by the year 2050, demographers forecast.
Some fear that this is gradually undermining China's economy. Wang Ming, a sociologist at Beijing Tsinghua University, warns that from 2015 on the percentage of working people will decrease rapidly.
Experts estimate that China's total labour force will decline by 11 per cent in the next 20 years and that its new entrants (those aged between 20 and 24) will drop by 45 per cent in the next 10 years.
"If the government holds on to the one-child-policy, the imbalanced population structure and ageing will heavily impact sustainable economic growth," Wang says.
The increasing pension and healthcare costs associated with an ageing population could also negatively impact the country's economic progress, he argues.
Today, three people work for every pensioner - in 20 years, the proportion of working to non-working people will be two to one.
The government may have succeeded in changing the traditional Chinese perception that having "more children [means] more happiness", but in a country where most elderly people rely on their children to support them, this generational imbalance is prompting its resurrection.
Guangdong, China's wealthiest province, quietly dropped the requirement that the "eligible-to-have-two-children couples" should wait for four years before having the second child.
Song, a manager from Beijing, says that he did not want to wait until the government policies changed.
"I already had a son, but I also wanted a girl. I have a good job and I could afford to pay the fine, but I am getting older and don't want to be alone," he says.
Many Chinese are worried about what they call "generation 4-2-1", where two parents have to support four grandparents and one child.
Time to change?
|Posters promote the country's one-child policy [EPA]
"When the one child policy was introduced, it was appropriate, because it suited China's limited resources," Hu Angang, an economics professor and government advisor from the Chinese Academy of Social sciences, wrote recently.
"But at the current state of development strict restrictions are not as necessary as before."
The one-child policy was initially supposed to last for 30 years. That would put it on course to end this year.
But China's National Population and Family Planning Commission has announced that it will also be implemented in the next five-year-plan, which runs from 2011 to 2015.
And if even the government were to abandon the policy, it might be difficult to change perceptions among those who have grown up with it and believe in its benefits.
Yang Juhua from the Population Research and Development Center at Beijing's People's University of China says the one-child policy has improved educational achievement.
"I find a consistent, strong advantage of single children in school enrollment and grade completion relative to those with an older brother or two plus siblings among children beyond compulsory education, regardless of residence and child gender. The 'quality' of children decreases with quantity, particularly with the presence of an older brother," Yang says.
"One of the purposes of the one-child policy in China is to improve child wellbeing. The government has taken strenuous effects to ensure that couples limit their fertility in exchange for high quality children - give birth to fewer children, but give them better care and education."
For those urban Chinese benefitting from rising living standards, restricting family size seems to make sense. In wealthy hubs like Shanghai the fertility rate (birth per woman) is currently 0.8 - far below the national average of 1.8.
Li Daiyu has a six-year-old daughter and says she never wanted more than one child.
"It wouldn't matter what my financial situation was or if they changed the law - I'd still only want one child," she says.
"One child is enough. I'm too busy at work to have any more. Also I want her to get a good education, to go to university, study and get a good job."