BEIJING, Jan. 11 (Xinhua) -- A report released here Thursday said there will be 30 million more males of marriageable age in China than females by the year 2020, which will make it difficult for men to find wives.

The report, issued by the State Population and Family Planning Commission, said China's sex ratio for newborn babies in 2005 was 118 boys to 100 girls, compared with 110:100 in 2000. In some regions, the sex ratio has reached 130:100.

"Discrimination against the female sex remains the primary cause of China's growing gender imbalance," said Liu Bohong, vice director of the women studies institute under the All-China Women's Federation.

Liu said that rural people in China are widely believed to be more "traditional", preferring sons to daughters, but the newborn gender imbalance is also widening in cities.

The Chinese capital Beijing saw 109 boys born for every 100 girls in the first 11 months of 2006.

Some couples, with a traditional preference for boys and only one chance to have a child, opt for abortion when they find out their unborn child is female. Many Chinese localities have outlawed fetus gender diagnosis to prevent the trend.

The report predicted that in the year 2020, Chinese men of marriageable age will find it difficult to find wives, especially those with low income or little education. This will create social instability.

Liu said the sex ratio imbalance was not connected to China's family planning policy. "It is more a result of the deep-rooted notion in Chinese culture that men are superior to women," she said.

In an attempt to halt the growing imbalance, China launched a "care for girls" campaign nationwide in 2000 to promote the belief that men and women are equal. The government has also offered cash incentives to girl-only families in the countryside. But these policies have not had their desired effect.

Experts believe China still has a long way to go before women can enjoy the same social resources and opportunities as men.