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Abnormalities in Puberty - part 2

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Ảnh hưởng bất lợi về môi trường cũng ảnh hưởng đến phát triển nam. Trong thời gian decennia qua, tỷ lệ mắc hypospadia và tinh hoàn không xuống sẽ xuất hiện gia tăng. Ở nam giới trưởng thành này có thể dẫn đến giảm chất lượng tinh trùng và khả năng sinh sản | Adverse environmental influences also affect male development. During the last decennia the incidence of hypospadia and undescended testes appears to increase. In adult men this may have led to decreased semen quality and fertility 46 . The bioactivity of these drugs appears to maintain for a long period of time. This can be explained by storage of these drugs in fat and other tissues or by a persistent effect by a changed programming of different organs. Generation studies should give more insight as to how environmental influences interfere with development and reproduction. Puberty Disorders In Europe precocious puberty is defined in girls as a start of breast development below the age of 8 years and in boys growth of testes with a volume equal to or more than 4 ml below the age of 9 years 47 . The studies of Herman-Giddens and coworkers provoked a discussion on whether these age limits still hold and if different limits should be used for white and black American children. It was recommended to use age limits of 7 years in white and 6 years in black girls 48 . However since the pubertal onset has advanced but not the timing of menarche the question can be addressed whether the cases of early puberty reflect a change in normal physiologic development or an abnormal puberty. This discussion is critical for the consideration of who needs to undergo diagnostic evaluation and therapeutic intervention. In 223 girls with breast development before the age of 8 years it appeared that one third had seriously advanced bone age and 12 had other endocrine disorders such as among others McCune-Albright syndrome adrenal hyperplasia and growth hormone deficiency 49 . These data are very important and show that early breast development between the ages of 6 and 8 years is not necessarily a benign variant and therefore still needs diagnostic evaluation. The development of sex characteristics in central precocious puberty is the result of a too early start of the GnRH pulse .