Question
Read the article and use the information to answer the following questions.
Puberty
When does puberty occur? What causes the changes that occur during puberty?
Puberty
When does puberty occur? What causes the changes that occur during puberty?
Answers
Answered by
GPT-5 mini
Puberty is the process of physical, hormonal and reproductive maturation that turns a child into an adult capable of sexual reproduction.
When it usually occurs
- Girls: typically begins between about 8 and 13 years (first sign usually breast budding). Menarche (first menstrual period) most often occurs around 11–14 years (average ~12–13).
- Boys: typically begins between about 9 and 14 years (first sign usually testicular enlargement).
- Timing varies widely between individuals and populations; some start earlier or later and still develop normally.
What causes the changes of puberty
- The central trigger is reactivation of the hypothalamic–pituitary–gonadal (HPG) axis:
- The hypothalamus begins to release gonadotropin-releasing hormone (GnRH) in a pulsatile pattern.
- GnRH stimulates the pituitary to secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
- LH and FSH stimulate the gonads (ovaries or testes) to produce sex steroids (estrogens in girls, testosterone in boys) and to mature gametes.
- Rising sex steroid levels produce the secondary sexual characteristics (breast development, genital growth, body hair), growth spurt, and changes in body composition.
- Adrenarche (maturation of the adrenal glands) also occurs and increases production of weak androgens (DHEA/DHEA‑S), causing pubic and axillary hair and body odor; adrenarche often precedes or accompanies gonadarche.
- Other contributing factors: genetics, body composition/nutrition (higher body fat and leptin levels can advance onset), overall health, and environmental influences (e.g., socioeconomic factors, some endocrine-disrupting exposures). There has been a trend toward earlier puberty in some populations, likely related to nutrition and obesity.
If you want, I can give a simple timeline of common physical changes in girls and boys or explain how growth spurts and emotional changes fit into the process.
When it usually occurs
- Girls: typically begins between about 8 and 13 years (first sign usually breast budding). Menarche (first menstrual period) most often occurs around 11–14 years (average ~12–13).
- Boys: typically begins between about 9 and 14 years (first sign usually testicular enlargement).
- Timing varies widely between individuals and populations; some start earlier or later and still develop normally.
What causes the changes of puberty
- The central trigger is reactivation of the hypothalamic–pituitary–gonadal (HPG) axis:
- The hypothalamus begins to release gonadotropin-releasing hormone (GnRH) in a pulsatile pattern.
- GnRH stimulates the pituitary to secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
- LH and FSH stimulate the gonads (ovaries or testes) to produce sex steroids (estrogens in girls, testosterone in boys) and to mature gametes.
- Rising sex steroid levels produce the secondary sexual characteristics (breast development, genital growth, body hair), growth spurt, and changes in body composition.
- Adrenarche (maturation of the adrenal glands) also occurs and increases production of weak androgens (DHEA/DHEA‑S), causing pubic and axillary hair and body odor; adrenarche often precedes or accompanies gonadarche.
- Other contributing factors: genetics, body composition/nutrition (higher body fat and leptin levels can advance onset), overall health, and environmental influences (e.g., socioeconomic factors, some endocrine-disrupting exposures). There has been a trend toward earlier puberty in some populations, likely related to nutrition and obesity.
If you want, I can give a simple timeline of common physical changes in girls and boys or explain how growth spurts and emotional changes fit into the process.
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