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Is China in the middle of a sperm crisis? New statistics reinforce the growing belief that Chinese men join the developed world by producing less sperm in their sperm, a trend that raises questions about their fertility in a country that is trying to increase its birth rate. Shanghai-based Fudan University sperm, which opened in June, barely 10% of sperm collected from more than 100 donors under 35 years of age met the bank's quality standards, local media reported.
The drop in quality was evident at the 15-year-old Shanghai Human Sperm Bank of Renji Hospital, where 25% of sperm collected from donors last year was acceptable, compared with more than 40 % in 2013.
And the sperm bank of the Third Beijing University Hospital in Beijing had less than 20% of samples taken from September 2015 to May 2016. What is happening in China seems to correspond to what researchers have discovered in the developed world. Last year, a study suggesting that the number of male sperm in Western countries had decreased by 50% in nearly 40 years had sparked a lively world debate.
A meta-badysis of more than 180 research articles published from 1973 to 2011 revealed a 52% decrease in sperm concentration and a 59% decrease in total sperm count in men in North America, Europe, in New Zealand and Australia. while China is facing enormous challenges with its new births in decline and that a quarter of the population is expected to be over 60 by 2030.
Its rapidly aging population has pushed Beijing to end the notorious single child policy – introduced in 1979 to control population growth – in 2016, and couples can now have two children.
Despite this new policy, only 17.6 million babies were born in Mainland China last year, compared to 241 million people over 60, Xinhua reported in June, citing figures from the National Commission of China. the health. said Qi Guangchong, andrologist of Shanghai Yueyang Hospital for Traditional Chinese and Western Integrated Medicine.
On the basis of an international review of male semen whose partners had been designed 12 months after the first test, the World Health Organization suggested that "normal" human semen now contains At least 15 million spermatozoa per milliliter and at least 40 per hundredth of motility (the ability of organisms and fluids to move or move). Almost 40 years ago, when the first edition of the WHO laboratory manual for the examination and treatment of human sperm was published, the lower limit of sperm production in the Member States by milliliter was 60 million and the mobility rate 70%.
The publication has been updated four times since and the standards according to which WHO judges the acceptability of sperm have been lowered.
In China, sperm banks are now following the Ministry of Health's guidelines, similar to those set by the WHO four decades ago, setting the sperm count at 60 million sperm per milliliter and motility. at 60%. A real problem in China, the statistical decline in sperm quality partly reflects the stricter quality standards imposed by China compared to much of the world, Qi said.
"Because the cost of getting a sperm donation [in China] is quite high, [owing to] physical and psychological exams, donor compensation, et cetera, sperm banks should make the most of each sample, "Qi said. "They need a better quality semen than what is normally required to put a pregnant woman."
So, what could have hurt male swimmers? Studies by researchers around the world have identified more than a dozen possible culprits. Professor Wang Guomin, expert in the male reproductive system at Shanghai Zhongshan Hospital, said that chemicals, ionizing radiation, heat, smoking and alcohol are one of the suspects usual.
"In a context of rapid industrialization, we are exposed to a large amount of chemicals in our daily lives via the consumption of medicines, food, cosmetics, etc.," he said. . These chemicals can disrupt the endocrine system – for glands that directly secrete hormones or other products in the blood – or create a "genetic change". Other pollutants potentially destructive sperm come from the burning of waste, the widespread use of pesticides and the emission of industrial production – factors that have been linked to the emergence of cancer, he said.
Infertility, a test experienced by both men and women, is causing more and more concern in China.
The official rate of infertility among married couples ranges from 10% to 15% today, compared with 3% more than 20 years ago, according to studies from the Chinese Population Association. In contrast, the Centers for Disease Control Prevention in the United States has suggested that infertility rates in the country may have declined between 1982 and 2010. The National Public Health Institute found that there was no evidence that infertility rates in the country could have declined between 1982 and 2010. Infertility affected 2.4 million women in 1982, compared with 1.53 million in 2010.
But Wang Wenjun, deputy head of the Reproductive Center at Sun Yat-sen Memorial Hospital in Guangzhou, said these figures did not accurately measure the growth of infertility in China. "Two decades ago we had a lot less medical resources and people were not leaving. solve their infertility problems, "she said. "But in general, we are seeing increasing infertility."
Some experts nevertheless criticize the validity of existing studies and the decline in the number of sperm suggesting an increase in male infertility.
Wang Guomin, a reproductive expert at Zhongshan Hospital, said the widely quoted meta-badysis published in the journal Human Reproduction Update was based on old studies from different regions. The research probably contained unmeasured variables or confounding factors that could have influenced the results, he said.
"To look more closely at the issue, we should be doing new experiments specifically designed to test men's sperm for 20 years, for example, preferably on sperm donors and men who conceived less than six months after having tried, "he said.
Wang Wenjun, a reproductive expert in Guangzhou, said that although the results may well represent the health status of the general public, the number of sperm cells in these studies remained well within the normal range or was sufficient to to make a pregnant woman fall.
"Therefore, a decrease in the number of sperm is not equivalent to a decline in male fertility," she said. Morning of South China.
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