Key findings: Prenatal sex selection results in distorted sex ratios at birth (SRB). In many countries there are currently 110-120 male births per 100 female births (in contrast to the standard biological level of 104-106 male births). Postnatal sex selection also persists in several countries, measured by excess deaths among female infants and young girls. Sex selection is prevalent not only in China and India, but also in other Asian countries, such as Vietnam and Taiwan. Such practices are more common in higher birth orders (second and upward), particularly if the first child is a girl.
Son preference is commonly cited as the primary factor behind sex selection. In order to understand the origins and persistence of son preference, it is important to look at the drivers of sex selection, which can be divided into two categories: social norms and structures; and the characteristics of the individual woman and her household. In the first case, son preference is commonly associated with the patriarchal societies of many Asian countries. There is, however, debate about the extent to which religion plays a role in son preference and the influence of caste in India. Regarding household and individual characteristics, for example legal limits on family size have been identified as drivers of sex selection. The role of socio-economic status has also been widely discussed.
Enabling and preventive factors include the following.
- Technology: wide diffusion of prenatal sex selection technologies and services across many Asian countries in recent years have contributed to the rise in SRB. In some countries, a rise in private health care and the increasing purchasing power of the growing middle classes have been integral to the spread of new technologies.
- Legislation: efforts to address the supply side of sex selection have included legal restrictions on the use of technology for sex determination or selection. However, such legislation has not been strictly enforced, thus undermining its effectiveness.
- Social change and economic development: South Korea is frequently cited as a success story, because the normalisation in sex ratios at birth is attributable to the country’s rapid development and modernisation, whereby rapid economic development, increased urbanisation and social change eroded the societal structures, norms and values that underpinned son preference and gender inequality.
