Which hormone is not essential for fetal growth according to studies cited?

• A. Glucose
• B. Insulin
• C. Thyroid Hormone
• D. Human Growth Hormone

Answer: (D)

Fetal growth is driven by insulin signaling in response to glucose and by thyroid hormone for proper metabolic maturation; human growth hormone is not required for fetal growth. Glucose reaches the fetus through the placenta, and the fetal pancreas responds with insulin, which acts as a major growth-promoting factor in utero. Thyroid hormone supports normal growth and development during gestation. In contrast, growth hormone’s major growth-promoting effects emerge after birth, and fetal growth can proceed normally even with limited GH activity. Placental GH can influence maternal IGF-1, but it does not drive fetal size. So the hormone not essential for fetal growth is human growth hormone.