Male fertility is falling every year in the Western world -- and experts blame chemicals and modern lifestyles.

西方国家男性的生育能力逐年下降--专家将其归因于化学产品和现代生活方式。

A study of 124,000 men visiting fertility clinics in Europe and the USA found sperm¹ quality reducing by almost 2% per year.

一项对欧洲和美国造访生育诊所的12.4万名男性进行的研究发现，精子质量正以每年2%的速度下降。

Separate research focusing on 2,600 sperm donors² (men with above-normal fertility) showed a similar pattern.

对2600名精子捐献者（生育能力高于正常水平的男子）进行的另外一项研究显示了相似的情况。

While most men can still father a child, scientists say the human race faces extinction³ if the trend continues.

尽管大多数男子仍能生育出一个孩子，但科学家称，如果这一趋势继续下去，人类将面临灭绝。

It follows a landmark⁴ study last year showing a 59% cut in Western sperm counts from 1973 to 2011.

在去年进行的一项具有里程碑意义的研究显示，从1973年到2011年，西方男性精子数减少了59%。

Pesticides⁵, hormone-disrupting chemicals, stress, smoking and obesity⁶ are seen as causes, along with too much alcohol, caffeine and processed meat.

杀虫剂、干扰荷尔蒙的化学品、压力、吸烟、肥胖、过量饮酒、咖啡因和加工肉类都被认为是精子减少的原因。

The chemicals include some used to make plastics flexible and furniture flame-retardant -- which can enter the food chain via plants or animals.

化学品包括一些使塑料有柔韧性的物质以及家具阻燃剂--这些物质可通过植物或动物进入食物链。

Experts also blame increases in testicular cancer, the number of boys born with one or both testicles missing, and changing testosterone levels.

专家还认为，睾丸癌患者人数的增加、男孩天生缺少一个或两个睾丸以及睾丸激素水平的变化都与此有关。

Scientists in Valencia, Spain,and New Jersey⁷, USA, carried out the first large-scale study of "swimming" sperm, known as the total motile sperm count.

西班牙巴伦西亚的科学家和美国新泽西州的科学家对“游动”精子（即活动精子总数）进行了首次大规模研究。

Men were split in to three groups with low, medium and high counts. The TMSC of those in the highest US group declined by 1.8% each year.

男子按精子数的低、中、高分成三组，在美国，精子数最高的那组人的活动精子总数每年下降1.8%。

The findings are causing alarm at an American Society for Reproductive Medicine meeting in Denver, Colorado, this week.

本周在科罗拉多州丹佛举行的美国生殖医学学会会议上公布的这一结果给人们敲响了警钟。

Co-author Dr James Hotaling said: "There is potential for more men to become infertile⁸ and that is concerning."

该研究共同作者詹姆斯·霍达灵表示：“可能会有越来越多的男子变得不能生育，这令人非常担忧。”