Growth and puberty: the GH-IGF-1 axis and pubertal development
How GH acts directly and through IGF-1, why IGF-1 is the screening test and a stimulation test the diagnostic one, mid-parental height and bone age worked through, how the HPG axis reawakens at puberty, the normal timing and sequence of puberty, why oestrogen closes the growth plates in both sexes, and how delayed and precocious puberty are separated by gonadotrophins.
Tier 2Medical sciences concept
Written with AI assistance and fact-checked against the sources below. For exam study, not clinical decisions. How notes are made
At a glance
- GH is released in pulses from somatotrophs under GHRH (stimulates), somatostatin (inhibits) and ghrelin. Most comes in slow-wave sleep.
- GH works directly (lipolysis, insulin antagonism) and through IGF-1, made mostly in the liver, which drives growth-plate chondrocytes and feeds back on the hypothalamus and pituitary.
- IGF-1 screens; dynamic tests diagnose. Suppression testing (OGTT) confirms excess and stimulation testing confirms deficiency.
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Sources
- Guidelines for growth hormone and insulin-like growth factor-I treatment in children and adolescents. Grimberg A et al. Horm Res Paediatr 2016;86:361-97Pediatric Endocrine Society, 2016
- Evaluation and treatment of adult growth hormone deficiency: an Endocrine Society clinical practice guideline. Molitch ME et al. J Clin Endocrinol Metab 2011;96:1587-609Endocrine Society, 2011
- Growth Hormone ProgramAU/NZAustralian Government Department of Health, Disability and Ageing (PBS), accessed November 2026
- Williams Textbook of Endocrinology, 15th editionElsevier, 2024
- CDC 2000 growth charts: stature-for-age percentile dataCenters for Disease Control and Prevention, 2000
- Last updated
- 14 November 2026
What changed
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