歐美男孩青春期提前 12歲就性成熟
It's not just girls: Boys are now hitting puberty a year earlier, finds study. Boys are on a faster track to puberty reaching the milestone an average year earlier than their fathers' generation, a study has found。
A study in Bulgaria found boys today start to develop at 12 years old, while those in the 1970s began changing when they were aged 13.
The findings suggest that trends towards earlier puberty aren't limited to girls, who have already been shown to be developing sexually at increasingly younger ages。
Researchers from Cedars Sinai Medical Center in Los Angeles compared 6,200 healthy boys with a similar 1970s study。
In the study, reported in the Archives of Pediatrics and Adolescent Medicine, they measured height, weight, testicular volume, penis length and circumference。
Study leader Dr Fnu Deepinder: 'Studies done several decades ago in the same population reported that a leap forward in sexual development occurs at ages 13 through 16.''However, our study indicated that this spurt takes place between 12 and 15 years old.'
有研究表明，青春期提前已不在是女孩子的“專利”了，之前有調查顯示，男孩的性成熟年齡已經越發提前。來自洛杉磯的科學家們測量了 6200例健康男孩的身體數據，其中包括身高、體重、睾丸體積、陰莖長度與周長，再將之與上世紀七十年代的數值進行了比較，結果表明，男孩在13到16週歲間性發育已經成熟，提前了很多，據研究的負責表示，現在的性成熟年齡已經提前到了12到15週歲之間。
The team found that boys' testicles did not grow substantially until the beginning of puberty, around age 11. However, penises appeared to grow gradually from birth to sexual maturity, starting at around 2 inches and reaching an average length of nearly 4 inches by the age of 19.
該研究小組發現，男孩們的睾丸自十一歲起開始快速發育，陰莖長度也日趨成熟，從出生時的兩英寸發育到了十九歲時平均四英寸的程度。
However, both penises and testicles grew most rapidly between ages 12 to 16, while boys added the most inches in height and gained the most weight between 12 and 14 years old。
儘管如此，陰莖與睾丸的發育高峯期出現在12到16歲間，而另一方面，男孩們長個子與體重的增加黃金時期則是12到14歲之間。
The study fund that boys of the same age in the 1970s study had relatively smaller genitalia. However, these size differences disappeared between the two generations by the age of 17.
研究中還發現，與如今同年齡段的男孩比較，上世紀七十年代的男孩生殖器相對較小，但兩代人的這一差異在17歲時便消失了。
Dr Deepinder said that genetic, environmental, nutritional and educational factors could all be behind the faster development today, but it remains unclear what impact earlier puberty might have on men's health。
負責人表示，遺傳、環境、營養以及教育等方面的變化都是促成發育提前的因素，但對於性早熟爲否對男性健康造成影響，目前還不得而知。
