Brundtland G H, Walloe L
Ann Hum Biol. 1976 Jul;3(4):363-74. doi: 10.1080/03014467600001581.
A fall in the age of menarche during the last fifty years is well documented from many parts of the world, among them Norway. Tanner says that this trend can be extended back at least to the middle of the last century, and he uses Norwegian sources to support this hypothesis. Re-examination of these Norwegian sources indicates that there was no fall at all during the ninetheenth century, and that the age at menarche was constant at approximately 16.0 years for the lower social classes throughout this period. It is also suggested that the age at menarche was constant at approximately 14 years for the higher social classes.
在过去的五十年里，世界上许多地区，包括挪威，都有充分的文献记载初潮年龄有所下降。坦纳表示，这一趋势至少可以追溯到上世纪中叶，他引用挪威的资料来支持这一假设。对这些挪威资料的重新审视表明，在19世纪根本没有下降，而且在这一时期，较低社会阶层的初潮年龄一直保持在大约16.0岁。还有资料显示，较高社会阶层的初潮年龄一直保持在大约14岁。
