Puberty

Puberty is the period of life at which the reproductive organs in both sexes begin to be functionally active, and is marked by other important changes in the structure and functions of the body. Among the peoples of northern Europe it begins in girls at from twelve to fourteen, and in boys about two years later. In girls both growth and development are about this period much more rapid than in boys; the breasts enlarge, and the figure becomes full; the temperament changes; and the menstrual flow begins to appear. In boys the most obvious changes are the breaking of the voice and the growth of hair on the face. The changes begun at this time are not fully completed nor the bodily and mental vigour of adult life established for at least eight or ten years after the commencement of puberty. The health during this period is specially liable to be disturbed by adverse influences, particularly in the female sex; and overstrain, both of the physical and mental powers, should be carefully guarded against.