Puberty is a period of rapid growth and physical change, during which adolescents become sexually mature. The age at which puberty begins and the rate of growth are influenced by genetics, general health, and weight. Puberty begins when the pituitary gland, located at the base of the brain, secretes hormones that stimulate the production of sex hormones. Within about 2 years of the start of puberty, sexual reproduction is possible, but it takes longer for adolescents to become mature enough emotionally for adult relationships.
In girls, puberty begins between the ages of 10 and 14, when luteinizing hormone (LH) and follicle-stimulating hormone (FSH) stimulate the ovaries to secrete the sex hormones oestrogen and progesterone. These hormones prompt physical changes and, later, stimulate ovulation and menstruation.
In boys, puberty usually begins between the ages of about 12and 15, when the pituitary gland starts to secrete the hormones LH and FSH. These hormones stimulate the testes to secrete the male sex hormone testosterone, which prompts physical changes and, later, sperm production and increased sex drive.
From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.