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How do thyroid hormones, insulin, and sex hormones affect physical growth?

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Fetal growth — human development Growth of the human fetus from the fourth month to the ninth month of pregnancy.

Hormones play a critical role in regulating human physical growth and skeletal development through various metabolic and physiological pathways.

Thyroid Hormones

Thyroid hormone is essential for normal growth and skeletal maturation, primarily by facilitating cell metabolism. While it does not directly stimulate growth in the absence of pituitary growth hormone, its deficiency leads to significant developmental retardation, such as stunted growth and impaired brain development in children. Conversely, excess thyroid hormone in the young can cause the premature appearance of ossification centers and the early closure of epiphyses, which ultimately limits potential height.123

Insulin

Insulin supports tissue development and is involved in the regulation of bone growth. It is believed to be necessary for the full effect of growth hormone on bone, as it promotes the synthesis of chondroitin sulfate in cartilage and bone, while also facilitating the transport of essential nutrients like amino acids into bone cells.13

Sex Hormones

Sex hormones are primary drivers of the adolescent growth spurt.3
* Testosterone: In males, it stimulates linear growth during puberty. However, high levels eventually suppress bone growth by hastening skeletal maturation and causing premature epiphyseal closure.12
* Estrogens: In females, these hormones contribute to the growth spurt and are responsible for specific skeletal changes, such as the widening of the hip. Estrogens also drive the eventual closure of the epiphyseal plates, which marks the end of longitudinal bone growth.213