Published 9 April 2009, doi:10.1136/bmj.b483
Cite this as: BMJ 2009;338:b483

Editorials

Ratio of males to females in China

Is still high, but only partly because of the one child policy

China’s one child policy is one of the most controversial social policies ever implemented. The policy reduced the fertility rate and has helped raise living standards for most people in China, but it has been heavily criticised for violating human rights and having many negative social consequences, one of which is an excess number of male births.¹

In the linked study (doi:10.1136/bmj.b1211), Zhu and colleagues assess trends and geographical patterns in the sex ratio at birth and in people under 20 years of age in China, in addition to the influence of sex selective abortion and the one child policy.² They find that in 2005 China had more than 32 million excess males under the age of 20, and over 1.1 million excess male births. The authors present a discouraging picture of very high and worsening male to female ratios in the reproductive age group in China for the next two decades.

By showing that sex ratios for different age groups and places of residence vary with how the one child policy is implemented, the study confirms that the policy is partially responsible for the current imbalance in the sex ratio in China. However, given that the policy is not an independent factor, the extent to which it accounts for the high male to female sex ratio is uncertain.

China, like other East Asian countries, has a cultural tradition of a preference for sons. In these countries, people think that only sons can continue the family line, and sons—rather than daughters—are responsible for their parents in illness and old age. Although it is well documented that this preference for sons is the cause of the high male to female ratio,³ the preference itself does not directly lead to this high ratio. A preference for sons can affect the sex ratio only in the presence of widespread access to sex selective technology (for example, ultrasound) and a reduced fertility rate (by choice or by coercion). When large family size is the norm and access to contraception is limited, a preference for sons increases the fertility rate but has little effect on the sex ratio. When family sizes are small, irrespective of whether this is voluntary or compulsory, a preference for sons encourages the use of sex selection to ensure the desired number of sons are born.⁴

The tradition of a preference for sons was mainly responsible for China’s high birth rate in the past, when large family size was normal and access to contraception and sex selective measures was limited. The one child policy was introduced to bring the high rate of population growth under control through fostering a culture of voluntarily having a small family. However, the policy itself is only partially responsible for the reduction in the total fertility rate. From the 1970s, before the policy was imposed, China saw an emerging culture of having a small family as a result of social and economic developments. The most dramatic decrease in the fertility rate, from 5.9 to 2.9, occurred between 1970 and 1979.⁵ After the one child policy was introduced in 1979, the rate fell more gradually, and since 1995 it has stabilised at around 1.7.⁶ It has therefore been suggested that China’s total fertility rate would have decreased even without the one child policy.¹ This large reduction in the fertility rate, whether by choice or by coercion, has inevitably increased the male to female ratio because of the preference for sons and the availability of contraception and sex selective measures. These changes in the sex ratio would probably have occurred even without the one child policy, but their effects would probably have been less serious.⁷ This idea is supported by neighbouring countries in East Asia, which have no restriction on family size but have the same preference for sons as China; these countries have some of the lowest total fertility rates in the world but also have extremely high ratios of boys to girls at birth.¹

China’s high ratio of males to females would have persisted if attitudes towards female offspring had not changed.⁷ Encouragingly, it seems that the tradition of preferring sons is shifting with the socioeconomic changes that come with urbanisation and industrialisation. For example, more and more young women in the cities claim to prefer a small family, and—more importantly—they have no preference for one sex over the other.⁸ Indeed, Zhu and colleagues report a decrease in the male to female ratio for the 2005 cohort,² which may indicate the beginning of a reduction in the male to female sex ratio for the future.

China can learn much from its neighbouring countries about reversing the worsening sex ratio. Korea was the first country to report very high male to female ratios at birth because of the preference for sons and the widespread use of sex selective technology. In 1992, the male to female ratio for fourth births in South Korea was an astounding 229:100, in sharp contrast to the overall ratio of 114:100. From the mid-1990s, however, a public awareness campaign warning of the dangers of such distortion, combined with strictly enforced laws forbidding sex selection technology, has led to a decline in the male to female ratio from 116:100 in 1998 to 110:100 in 2004.⁴

Cite this as: BMJ 2009;338:b483

¹ The Second Teaching Hospital, Jilin University, Changchun 130041, PR China

Research, doi:10.1136/bmj.b1211

---

Competing interests: None declared.

Provenance and peer review: Commissioned; not externally peer reviewed.

References

1. Hesketh T, Lu L, Zhu WX. The effect of China’s one-child family policy after 25 years. N Engl J Med 2005;353:1171-6.[Free Full Text]
2. Zhu WX, Lu L, Hesketh T. China’s excess males, sex selective abortion, and one child policy: analysis of data from 2005 national intercensus survey. BMJ 2009;338:b1211.[Abstract/Free Full Text]
3. Hesketh T, Zhu WX. Abnormal sex ratios in human populations: causes and consequences. Proc Natl Acad Sci USA 2006;36:13271-5.
4. Park CB, Cho NH. Consequences of son preference in a low fertility society: imbalance of the sex ratio at birth in Korea. Pop Dev Rev 1995;2:59-84.
5. Hesketh T, Zhu WX. The one child family policy: the good, the bad, and the ugly. BMJ 1997;314:1685-7.[Abstract/Free Full Text]
6. Wang JY. Evaluation of the fertility of Chinese women during 1990-2000. In: Theses collection of 2001 national family planning and reproductive health survey. Beijing: China Population Publishing House, 2003:1-15.
7. Ding QJ, Hesketh T. Family size, fertility preferences, and sex ratio in China in the era of the one child family policy: results from national family planning. BMJ 2006;333:371-3.[Abstract/Free Full Text]
8. Lin B. Fertility desires of women of childbearing age and influencing factors. In: Theses collection of 2001 national family planning and reproductive health survey. Beijing: China Population Publishing House, 2003:57-65.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    StumbleUpon    Technorati    What's this?

Relevant Articles

China’s excess males, sex selective abortion, and one child policy: analysis of data from 2005 national intercensus survey

Wei Xing Zhu, Li Lu, and Therese Hesketh
BMJ 2009 338: b1211. [Abstract] [Full Text] [PDF]

Family size, fertility preferences, and sex ratio in China in the era of the one child family policy: results from national family planning and reproductive health survey

Qu Jian Ding and Therese Hesketh
BMJ 2006 333: 371-373. [Abstract] [Full Text] [PDF]

Health in China: The one child family policy: the good, the bad, and the ugly

Therese Hesketh and Wei Xing Zhu
BMJ 1997 314: 1685. [Abstract] [Full Text]

Rapid Responses:

Read all Rapid Responses

Don't mention the 'A' word

Robert P. Balfour
bmj.com, 19 Apr 2009 [Full text]

Are we sure China's lopsided sex ratio is a problem?

Wayne E Thogmartin
bmj.com, 24 Apr 2009 [Full text]

Online poll

Find out more >>