|Chinese girls are more likely to be placed in orphanages than boys [File: EPA]
China's one-child policy was adopted in 1979 to limit population growth in the world's most populous nation.
Under the system, parents face fines if they conceive a second child.
However, there are exceptions to the one-child policy.
Families in rural areas are largely permitted to have a second baby if their first is female or disabled, while people who marry and have no siblings can seek permission from the government to have two children, maintaining zero population growth.
Although officially designated as a "temporary measure", the one-child policy is still in place nearly three decades later.
In March 2008, Zhang Weiqing, minister of the national population and family planning commission, said that no major changes would be made to the system for at least another decade.
Zhang told China Daily, the country’s official English-language newspaper, that 200 million people would enter childbearing age during that time and abandoning the policy could harm the population's stability.
"Given such a large population base, there would be major fluctuations in population growth if we abandoned the one-child rule now," he said. "It would cause serious problems and add extra pressure on social and economic development."
According to China Daily, 118 Chinese boys are born for every 100 Chinese girls. The natural ratio is 106 boys per 100 girls.
Since there are now methods of predetermining gender prior to giving birth, women who are pregnant with girls are more likely to abort them.
Girls are also more likely to end up in an orphanage, only one-fifth of children in orphanages are boys and the one-child policy makes it relatively easy for people outside of China to adopt Chinese girl babies and children.
High rates of infanticide also exist for girl babies born in urban areas.
But China has said that the policy has been successful in preventing 300 million births, the equivalent of the population of the United States.
Beijing told delegates at UN talks in Vienna in August 2007 that the measure had helped combat climate change, meaning there was less demand for energy and lower emissions of heat-trapping gases from burning fossil fuels.
An opinion poll published by the Pew Research Centre in August 2008, said that the one-child policy was overwhelmingly accepted by the Chinese public with 76 per cent of people surveyed approving.
Source: Al Jazeera