女孩男孩過早的青春期發育,禍從何來?

In the late 1980s, when Marcia Herman-Giddens was working in a paediatric clinic at Duke University Medical Centre in North Carolina she noticed a puzzling phenomenon. More and more girls aged eight or nine who visited the clinic had started to sprout breasts. At the time, medical orthodoxy held that the average age of puberty for girls in the west was over 11. The numbers of under-10s that Herman-Giddens was seeing did not fit with this scenario. She began collecting data that eventually produced a study with the American Academy of Pediatrics that studied 17,000 girls and found that the average age of breast-budding among white girls was 9.9 years while for black girls it was 8.8.
20世紀80年代末，馬西婭•赫爾曼-吉登斯在卡羅萊納州北部的杜克大學醫學中心的兒科診所工作時，她發現了一個令人費解的現象。越來越多來診所的八九歲女孩已開始出現乳房。當時，醫學正統界認爲西部女孩的青春期平均年齡在11歲以上。赫爾曼-吉登斯看到的衆多十歲以下的女孩並不符合這種情況。她開始收集數據，在研究17000名女孩之後最終與美國兒科學會得出了結論，發現白人女孩胸部發育的平均年齡爲9.9歲，而黑人女孩爲8.8歲。

The discovery was hugely controversial. Many doctors refused to accept the fact that more and more girls had begun to mature sexually before they had reached the age of 10. "The Lolita syndrome [the prurient fascination with the sexuality of young girls] created a lot of emotional interest," recalls Herman-Giddens, now at the University of North Carolina. "As a feminist, I wish it didn't."
該發現引發了巨大的爭議。許多醫生拒絕接受這樣的事實，即越來越多的女孩在她們到達10歲之前就開始性成熟。“洛麗塔情結（對小女孩的單純性迷戀）產生了很多情感興趣，目前在北卡羅萊納大學的赫爾曼-吉登斯回憶說。“作爲一個女權主義者，我希望事實並非如此。”

Today most doctors accept that the age of onset of puberty is dropping steadily. Many studies have showed this to be the case for girls, and new research carried out by Herman-Giddens, and published by the American Academy of Pediatrics, has found the same for boys. The age of onset of biological adulthood continues to plunge. Consider the statistics provided by German researchers. They found that in 1860, the average age of the onset of puberty in girls was 16.6 years. In 1920, it was 14.6; in 1950, 13.1; 1980, 12.5; and in 2010, it had dropped to 10.5. Similar sets of figures have been reported for boys, albeit with a delay of around a year.
今天，大多數醫生接受青春期開始的年齡在逐漸下降。許多研究都表明這正應對女孩的情況，由赫爾曼-吉登斯開展以及美國兒科學會公佈的新研究已發現這同樣適用於男孩。生理上的成年期開始的年齡繼續大幅下挫。考慮到德國研究人員提供的統計數據。他們發現，在1860年，女孩進入青春期的平均年齡爲16.6歲。1920年爲14.6歲，在1950年爲13.1歲，1980年,爲12.5歲，並在2010年已經降到10.5歲。男孩也報告了一組類似的數字，雖然有一年左右的延遲。

What factors lie behind this trend? Why are our children reaching biological adulthood at earlier and earlier ages? And what are the medical implications of this? Answers to these questions are still debated, although most scientists and health experts believe that the initial decline in the age in puberty was linked to general improvements in health in the west that began in the late 19th century. The trouble is that this drop, which was expected to stop, has simply continued at the same rate: a decline in four to five months in age of onset for each passing decade.
這一趨勢背後的因素是什麼？爲什麼我們的孩子達到生理成熟的年齡越來越早？這一現象的醫學暗示是什麼？對這些問題的答案仍存在爭議，儘管大多數科學家和健康專家認爲，在青春期年齡的初始下降與西方19世紀後期開始的健康條件的普遍改善有關。問題在於預計將停止的這個下降，只是還在以同樣的速度繼續：每10年發育年齡會下降4到5個月。

This relentless slide has begun to worry doctors who have proposed a host of causes to explain it. Increasing obesity is often quoted. In the young it is thought to increase blood levels of oestrogens that promote breast development and early studies seemed to confirm this by linking puberty to higher body mass index. However, a Danish study released last year in the journal Paediatrics found puberty occurring earlier in children regardless of body mass index at age seven.
這種無情的下滑已經開始使那些提出了很多原因來解釋它的醫生擔心。不斷增加的肥胖經常被作爲原因。它被認爲是增加了年輕人血液中的雌激素從而促進了乳房發育，早期的研究通過把青春期和較高的身體質量指數相聯繫似乎證實了這一點。然而，去年發表在兒科雜誌上的丹麥研究發現，不論身體質量指數如何，兒童的青春期七歲時就更早地發育了。

Other factors that may be involved include a diet that is increasingly high in sugar and fat and declining physical activity. The cause could also be environmental, say other researchers – in particular, exposure to endocrine disrupters, chemicals in the environment that act on hormones.
其他可能涉及到的因素包括飲食中越來越高的糖和脂肪以及身體鍛鍊的減少。也可能是環境的原因，其他研究人員說——尤其是暴露在環境中的內分泌干擾物以及化學物質影響到了荷爾蒙。

Widespread industrial and pharmaceutical pollutants have already been shown to harm the normal sexual development of fish and animals. By extension, they may also contribute to earlier or disrupted puberty in children, these scientists contend.
大範圍的工業和製藥業污染已被證明傷害了魚和動物的正常性發育。推而廣之，他們也可能導致孩子的青春期提前或中斷，這些科學聲稱。

As to the likelihood that precocious puberty poses perils for young people, this is still debated – though many parents worry that early sexual development puts strain on children who are being robbed of years of innocent childhood.
由於性早熟的可能性給年輕人帶來了危險，這仍然存在爭議——儘管許多家長擔心性早熟給孩子們造成壓力，他們正被剝奪掉天真無邪的童年。