BEIJING, April 10 -- The world's most populous nation is suffering lower fertility rates with up to 10 percent of Chinese couples unable to conceive because of stress and unhealthy lifestyles, reproduction health experts have warned.

    No large-scale infertility survey has been conducted in the country and statistics are hard to come by, but reports contributed by regional research bodies indicate an average infertility rate of between 7 percent and 10 percent among married couples, said Professor Wang Yifei of Shanghai Jiaotong University.

    Delaying childbirth until after a woman turns 35 and multiple abortions are often to blame for infertility and miscarriages. But Wang said male infertility was also on the rise in China, with sperm counts decreasing from an average 100 million per ml in the 1970s to 40 million per ml Tuesday. A sperm count of less than 20 million per ml is considered abnormal.

    "A certain percentage of the sperm donated by seemingly healthy college boys to our sperm bank in Shanghai is not eligible in terms of sperm count or motility," Wang said.

    Experts believe more than 10 million Chinese families need artificial fertilization and many are undergoing fertility treatment.

    A reproduction health specialist in Hangzhou, East China's Zhejiang Province, has attributed the rising infertility rates to stressful and unhealthy lifestyles linked to dramatic social and economic changes-including obesity, drinking alcohol, smoking and environmental problems.

    "The problem deserves attention from all walks of life because it threatens the quality and structure of our future population," said Huang Hefeng of Zhejiang University at an ongoing symposium on reproduction health in Hangzhou.

    Almost 1,000 researchers and doctors are attending the symposium to discuss a wide range of topics, including infertility, miscarriages and maternity and baby health.

    About 22 million babies are expected to join China's 1.3 billion population this year, the Year of the Golden Pig, which is considered auspicious for births, up from an average of 16 million a year from 2001 to 2006.

    But demographers have repeatedly warned of a graying society in China, where one out of every 10 people is over 60 years old and the ratio is expected to hit 30 percent by 2045.

    The government has said that creating welfare programs for its soaring numbers of elderly is a national priority, but warned that will be a daunting challenge in a society that is ageing before it becomes affluent.

    (Source: China Daily)