The Sex Ratio Imbalance in China

sex ratioIf you think it’s hard to find a girlfriend, spare a thought for the millennial generation of Chinese males. One of the consequences of the One-child policy has been a widening of the population sex ratio in China, meaning the gap between the number of males and the number of females. Many have wondered what the consequences of this sex ratio imbalance could be and how a society like China would respond to them.



The One-child policy

The One-child policy implemented in 1979 states that married couples in China are only legally allowed to have one child. Couples who have unauthorised children could be denied government aid, poverty assistance, access to farming materials, technology training programs, and even healthcare and education for their children.[1] There are a few exceptions to this policy (parent who are ethnic minorities, multiple babies but one birth, paying the fine for having a second child), but for most Chinese people all they will ever have is a three person family.


Add to this a culture that has a very strong male-preference and the pressure to have your only child be a strong, handsome, intelligent son and you have the conditions for a society where girls become rarer and rarer. While aborting a pregnancy for the reason of sex preference is illegal, this has not stopped a significant imbalance to emerge.

Of course this male preference is not as strong as it once was; in earlier times girls were often not given proper names. But the expectations placed on different gender roles continue and for parents having a son is better insurance in their old age when they need their children to take care of them. Don’t flatter yourselves, for most of human society this is a very real reason to have lots of children; not everyone has a cushy pension fund.


The growing imbalance, 1979−today

The result in China since 1979 has been a steadily growing gap between the numbers of males born to the numbers of females born. According to Chinese demographers, the people who study populations, the sex ratio in China right up until the 1980s remained at what is considered a normal level of 105-107 males per 100 females.[2]

This “normal” ratio has been observed since at least 1710 when it was first documented in London but has since been confirmed all over the world in differing societies and cultures.[3]

In the 1980s a massive divergence began to occur. As at 2014, in China there are an estimated 116 males per 100 females between the ages of 0 and 14 years, and 113 males per 100 females for those between 15 and 24 years of age.[4]

This national statistic masks the divergence in sex ratios between different provinces that are even more extreme. In the China One Percent Population Survey conducted in 2005, Shaanxi province had a ratio of 132 males to 100 females. If we take 115 males as the normal level than 18 of the 31 provinces surveyed are above this level and eleven are above 120 males to 100 females.[5]


Consequences of sex ratio imbalances

Other than the peculiar societal effects of having too many men running around and not enough women blocking them on WeChat, there is also a very interesting human security consequence.

The so called “bare branches” theory developed by two political scientists Andrea M. Der Boer and Valerie M. Hudson argues that artificially high sex ratios pose potentially grave security problems for societies and have done so previously in Chinese history.

Bare branches refer to males who will never be able to have families because they cannot find a spouse, not through lack of trying but because they simply are not enough. They are also likely to be in the lowest socioeconomic class and ‘floaters’ in terms of their mobility for they never have a reason to lay down roots in a single place to start a family.

In terms of economics, they are more likely to be underemployed or unemployed, performing dangerous, menial, labour intensive seasonal work. They usually do not have land or other resources to increase their marriage chances. Their most common route to gaining resources is through military service, they are “perennial aspirants in large-scale expansionist and insurgent military campaigns through which they might achieve higher positions”.[6]

In terms of behavioural tendencies of the bare branches, they are more likely than other males to turn to vice and violence. Men are more likely than women to commit violent crime, young men are more likely to exhibit anti-social behaviour than older men, and unmarried men commit more violence than married men.[7]

Others have made similar finding in the 1990s that societies with high proportions of males between 15 and 29 years old are much more prone to violence and instability.[8] All agree that the mere presence of more males does not cause more violence, just more opportunity for relatively large-scale violence to occur.[9]

A population that is more disproportionately male – even more than it is now – is likely to face greater problems in the future. Evidence that the bare branches theory has taken root so to speak exists with research finding migrant workers being responsible for the increase in violent crime.[10]  Hudson and den Boer also argue that the Chinese state will have to become more authoritarian over time to cope with the large-scale intra-societal violence created by the bare branches.

According to researcher Robert Wright “Few things are more anxiety-producing for an elite governing class than gobs of [unmarried] and childless men with at least a modicum of political power”.[11] The Chinese government has increased the size of the People’s Armed Police by 14 divisions, to about 1 million men in response to increased urban crime.[12]

Potential new security problems include the theory that governments with high sex ratio imbalances also tend to cultivate a swaggering, belligerent and provocative, martial style to retain the allegiance and respect of the bare branches.[13]

With the effective end of the One-child policy this year, the Chinese Government has finally sort to take action against some of the consequences of their 30 year policy of strict family planning. But until the numbers even out, Chinese men will continue to outnumber Chinese women for a few decades more. On the upside for Chinese women, they can be a lot more choosey about finding a husband, something that will make them quite powerful into the future. 

[1] Hudson, V. M. & den Boer, A. M. (2005). Bare Branches – The Security Implications of Asia’s Surplus Male Population. Cambridge, MA, USA: The MIT Press, pp. 152-4.
[2] Hudson, V. M. & den Boer, A. M. (2005). Bare Branches – The Security Implications of Asia’s Surplus Male Population. Cambridge, MA, USA: The MIT Press, pp. 157.
[3] Hesketh, T. & Xing, Z. W. (2006). Abnormal sex rations in human populations: Causes and consequences. PNAS Vol. 103, No. 36, September 5, 2006, pp. 13,271.
[4] CIA (2014). CIA World Factbook – China. Published by the Central Intelligence Agency of the United States of America. Retrieved online from:
[6] Hudson, V. M. & den Boer, A. M. (2005). Bare Branches – The Security Implications of Asia’s Surplus Male Population. Cambridge, MA, USA: The MIT Press, pp. 188-90.
[7] Ibid. pp. 192-5.
[8] Glenn, D. (2004). A Dangerous Surplus of Sons? The Chronicle of higher Education – Research and Publishing, 30 April 2004 edition, pp. 6.
[9] Hudson, V. M. & den Boer, A. M. (2002). A Surplus of Men, A Deficit of Peace – Security and Sex Ratios in Asia’s Largest States. International Security, Vol. 26, No. 4, Spring 2002, pp. 15.
[10] Ibid.
[11] Ibid. pp. 25.
[12] Ibid. pp. 33.
[13] Ibid. pp. 26.


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