More than 24 million Chinese men of marrying age could find themselves without spouses¹ by 2020, says the Chinese Academy of Social Sciences.

中国社会科学院称，超过2400万达到结婚年龄的中国男子在2020年将找不到自己的另一半。

In some provinces, 130 boys are born for each 100 girls

The gender² imbalance among newborns is the most serious demographic人口统计学的 problem for the country's population of 1.3 billion, says the academy.

It cites sex-specific abortions流产，堕胎 as a major factor, due to China's traditional bias偏见 towards male children.

The academy says gender selection abortions³ are "extremely common".

This is especially true in rural areas, and ultra-sound scans, first introduced in the late 1980s, have increased the practice.

Forced prostitution

The latest figures show that for every 100 girls born in China, 119 boys are born, the academy says in a new book.

Researcher Wang Guangzhou, quoted by the Global Times newspaper, said the implications were that men in poorer parts of China may remain single throughout their life.

"The chance of getting married will be rare if a man is more than 40-years-old in the countryside. They will be more dependent on social security as they age and have fewer household家庭的，日常的 resources to rely on," he said.

In some provinces, 130 boys are born for each 100 girls, the book says.

Experts at the academy also predict the gender imbalance will lead to more inter-generational marriages, where a wife is older than her husband.

A reluctance勉强，不情愿 among young urban Chinese to have a first or second child is exacerbating⁶恶化 the problem.

Academy sociologist⁷ Yan Hua said: "People's minds have changed a lot during the last 20 years.

"Young couples either don't want to have a second child, or would prefer to live a DINK (Double Income No Kid) life."

The growing imbalance means that forced prostitution卖淫 and human trafficking has become "rampant⁸猖獗的" in some parts of the country, according to the researchers.

While analysts⁹ admit there is definitely a pronounced gender imbalance in China, they also say that exact information is difficult to obtain because some families are thought to avoid registering female babies in order to make it easier for them to have a second child.