Le Thanh Hai Training Institution: Hanoi Medical University New conclusions of the thesis: 1 / The first comprehensive study on clinical, subclinical characteristics, causes and outcome of treatment central precocious puberty at a large sample size in a single center of Northern Vietnam (475 patients), the literature has only one study in France on the skin race white with the same sample size published; There is no large sample size study on Asian race as this study because the race is also an important factor in early puberty.