the development at an early age of the physical and physiological changes associated with puberty. In girls this is usually taken as development of breasts or pubic hair before the age of six or menstruation before the age of eight. In boys development of pubic hair or other adult sexual features below the age of nine is considered to be precocious. In girls 90% of cases have no underlying abnormalities, but in boys approximately half have a serious underlying cause, of which malignant testicular tumours and malignant adrenal tumours are the most common.
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onset of sexual maturation at an earlier age than normal, defined as two standard deviations below the mean, or before age 8 in girls and 9 in boys. It is usually hormonal (central precocious p.), but occasionally it occurs in otherwise normal children (constitutional precocious p.) Called also sexual precocity and pubertas praecox.Medical dictionary. 2011.