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Adolescence, generally between 12 and 19 years, is a time of complex physical, cognitive, psychosocial, and sexual changes, and physical development occurs in advance of cognitive maturity. Not until maturity is reached in all of these realms does the adolescent acquire mature decision-making skills and the ability to make healthy decisions regarding sexual activity. Sexuality involves more than just anatomic gender or physical sexual behavior, but incorporates how individuals view themselves as male, female, or other; how they relate to others; and the ability to enter into and maintain an intimate relationship on a giving and trusting basis. Adolescent sexual development forms the basis for further adult sexuality and future intimate relationships. Adolescents who are sexually active before having achieved the capacity for intimacy are at risk for unwanted or unhealthy consequences of sexual activity.


Physical Changes

Rapid changes in their bodies often make adolescents feel uncomfortable and self-conscious. Puberty usually starts between 9 and 12 years for girls and between 11 and 14 years for boys. In girls, these hormonal changes result in the development of breasts, growth of pubic and axillary hair, body odor, and menstruation (often irregular or unpredictable for the first 18–24 months). Boys develop increased penis and testicular size; facial, pubic, and axillary hair; body odor; and a deepened voice, and experience nocturnal ejaculations (“wet dreams”). As adolescents are learning to adjust and grow comfortable with their changing bodies, questions concerning body image are common (eg, penis size, breast size and development, distribution of pubic hair, and changing physique in general).

Cognitive Changes

The shift from concrete thinking to abstract thinking (the cognitive development of formal operations) begins in early adolescence (11–12 years) and usually reaches full development by 15–16 years, so 10- to 14-year-olds should not be expected to function with full capacity for abstract thinking. In contrast to younger children, adolescents:

  • Show an increased ability to generate and hold in mind more than one complex mental representation.

  • Show an appreciation of the relativity and uncertainty of knowledge.

  • Tend to think in terms of abstract rather than only concrete representations; they think of consequences and the future (abstract) versus a sense of being omnipotent, invincible, infallible, and immune to mishaps (concrete).

  • Show a far greater use of strategies for obtaining knowledge, such as active planning and evaluation of alternatives.

  • Are self-aware in their thinking and able to reflect on their own thought processes and evaluate the credibility of the knowledge source.

  • Understand that fantasies are not acted out.

  • Have the capacity to develop intimate, meaningful relationships.

Psychosocial Changes

Core psychosocial developmental tasks of adolescence include the following:

  • Becoming emotionally and behaviorally independent rather than dependent, especially in developing independence from the family.

  • Acquiring educational and other experiences needed for ...

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