Which statement about fetal growth hormones is true according to the material?

• A. The fetus requires Human Growth Hormone for normal growth.
• B. Growth is primarily driven by Glucose in the fetus.
• C. Insulin is the primary fetal growth-promoting hormone.
• D. Thyroid Hormone is the main driver of fetal growth.

Answer: (C)

Insulin is the primary fetal growth-promoting hormone. In the fetus, insulin from the pancreatic beta cells acts as a potent anabolic signal, promoting uptake of glucose and other substrates and driving tissue growth and fat deposition. Fetal insulin rises in response to glucose crossing the placenta, so maternal glucose levels influence fetal growth through this hormonal pathway. This explains why infants of mothers with diabetes can become macrosomic due to fetal hyperinsulinemia. Other hormones aren’t the main drivers of fetal growth: growth hormone is mainly a pituitary hormone and doesn’t significantly promote fetal growth, glucose is a needed substrate rather than the hormonal driver, and thyroid hormone supports maturation but is not the chief force behind fetal growth.