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A. Introduction

  1. Occurs between ages 8 and 20 years
  2. Consists of rapid changes in body size, shape, and physiology
  3. Accompanied by alteration in psychological and social functioning
  4. Combination of hormonally driven development with societal influences

B. Biologic Development

  1. In utero exposure to sex steroids primes tissue for later sex hormone responsiveness
  2. In prepubescent state, sex steroids are repressed by negative feedback on hypothalamus
  3. Onset of puberty heralded by reduction of hypothalamic inhibition in response to incompletely understood factors
  4. During sleep pulses of gonadotropins and growth hormone are released from the anterior pituitary
  5. Gonadarche results from central gonadotropin release
  6. Adrenarche stems from independent adrenal androgen production
  7. Initiates somatic and physiologic changes which constitute puberty

C. Growth

  1. Acceleration begins in early adolescence
  2. Peak velocity is reached by Tanner Stage III-IV
  3. Annual growth is double the prepubertal rate
  4. Growth spurt occurs earlier in girls than boys
  5. Asymmetric growth results in hands and feet enlarging earlier than trunk and chest
  6. Weight gain parallels linear growth with a delay of several months

D. Sexuality

  1. Interest in sexuality increases in early puberty
  2. Sexuality includes behaviors and fantasies as well as awareness of social roles and mores
  3. In boys, ejaculation starts after masturbation or during sleep by Tanner IV
  4. In girls, menarche occurs in 30% by Tanner Stage III and 90% by Tanner IV
  5. Initiation in sexual intercourse
    1. 13 years: 5% of girls and 20% of boys report having intercourse
    2. 16 years: 30% of girls and 45% of boys report having intercourse
  6. Adolescent has initial thoughts and experimentation with sexual orientation

E. Other Changes

  1. Androgens stimulate the sebaceous glands promoting development of acne
  2. Elongation of optic globe often causes nearsightedness
  3. In males, voice changes reflecting laryngeal and thoracic growth
  4. Transition from concrete operational thoughts to formal logistical operations
  5. Dramatic increase in self awareness and self consciousness
  6. Continued separation from family and increased reliance on peers

F. Tanner Staging - Females

  1. Breast (mean ages in years ± 2 standard deviations)
    1. Stage I: No breast development
    2. Stage II: Breast budding with increased aerolar diameter (8.9-12.9 years)
    3. Stage III: Breast and areola enlarge with no contour separation (9.8-13.8 years)
    4. Stage IV: Areola and papilla form secondary mound (10.5-15.3 years)
    5. Stage V: Mature female breast with nipple projecting and areola part of general contour (11.5-16.3 years)
  2. Pubic hair (mean ages in years ± 2 standard deviations)
    1. Stage I: Preadolescent
    2. Stage II: Sparse lightly pigmented pigmented hair concentrated on the medial border of the labia (9.0-13.5 years)
    3. Stage III: Darker, coarser and curlier hair with increased amount (9.6-14.4 years)
    4. Stage IV: Coarse, curly and abundant hair without spread to medial thigh (10.3-14.8 years)
    5. Stage V: Adult feminine triangle with spread to medial surface of thighs (11.4-17.3 years)

G. Tanner Staging - Males

  1. Pubic Hair (mean ages in years ± 2 standard deviations)
    1. Stage I: Preadolescent
    2. Stage II: Scant log pigmented hairs (9.9-14.1 years)
    3. Stage III: Darker hairs with initial curling (11.2-14.9 years)
    4. Stage IV: Resembles adult type with less in quantity (12.0-15.7 years)
    5. Stage V: Adult distribution with spread to medial surface of thighs (12.9-17.3 years)
  2. Penis (mean ages in years ± 2 standard deviations)
    1. Stage I: Preadolescent
    2. Stage II: Slight enlargement (9.2-13.7 years)
    3. Stage III: Further elongation (10.1-14.6 years)
    4. Stage IV: Growth in length and circumference of the penis and glans (11.2-15.4 years)
    5. Stage V: Adult size (12.8-17.4 years)
  3. Testes (mean ages in years)
    1. Stage I: Pre-adolescent
    2. Stage II: Enlargement in testes and change in texture of scrotum (10.4-13 years)
    3. Stage III: Further enlargement (12.6-14.0 years)
    4. Stage IV: Darkening of scrotal skin (13.6-15.8 years)
    5. Stage V: Adult size ( 14.8-16.2 years)

References

  1. Tanner JM and Davies PSW. 1985. J Pediatr. 107:317 abstract
  2. Slap GB. 1986. J Adolesc Health Care. 7:13S abstract
  3. Carel JC and L©ger J. 2008. NEJM. 358(20):2366