NANNING - China's population will hit 1.39 billion people over the next five years, posing greater challenges for the country's economic and social development, a family planning official said on Tuesday.

Major population challenges will include greater numbers of birth defects, unbalanced sex ratios and an aging society, said Cui Li, vice-minister of the National Population and Family Planning Commission, at the China-ASEAN forum currently being held in Nanning, capital of South China's Guangxi Zhuang autonomous region.

According to the sixth population census, China's population amounted to 1.37 billion as of November 1, 2010.

According to Cui, birth defects in China have increased in recent years, a fact that will influence China's labor supply in the future.

The birth defect rate in China has increased by over 70 percent since 1996, going from 87.7 defects per 10,000 births in 1996 to 149.9 defects per 10,000 births in 2010, the Ministry of Health said in a report issued earlier this year.

In response, the Ministry of Health in 2009 launched an early intervention program for pregnant women in rural areas to prevent congenital disorders. The program allows pregnant women to obtain free folic acid from three months before their pregnancy until three months after.

Cui also mentioned the constant growth of China's migrant population. Rapid urbanization boosted the migrant population to 221 million people as of the end of 2010.

Considering the complex and diverse issues related to the country's population, Cui said the government regards population as a strategic component for the development of its next Five-year Plan.

In the 12th Five-year Plan (2011-2015), the government stated that it will adjust its family planning policies to promote gender equity, manage unbalanced sex ratios and handle migration and aging by providing more public services.