A child’s growth from infancy to adulthood is a very complex process. Good nutrition, exercise and rest are all essential for healthy growth. Growth is regulated by many chemicals in the body called hormones. The most important hormone that controls growth is growth hormone. When the body does not produce enough growth hormone, it can affect a child’s growth rate, which is known as growth hormone deficiency. There are two types of growth hormone deficiency: a complete deficiency (no growth hormone is produced) and a partial deficiency (a small amount of growth hormone is produced, but it is not enough for the child’s growth). Why do children suffer from growth hormone deficiency? There are many factors that contribute to growth hormone deficiency in children. Three main factors can affect growth hormone production: Pituitary gland: Injury or disease can cause the pituitary gland to lose its ability to produce growth hormone. Hypothalamus: The hypothalamus secretes growth hormone-releasing hormone, which stimulates the pituitary gland to secrete growth hormone. If the hypothalamus does not secrete enough growth hormone-releasing hormone, the secretion of growth hormone will be affected. Body tissues and organs: may not be sensitive to growth hormone, even if there is enough growth hormone and growth hormone-releasing hormone in the body. What can cause growth hormone deficiency in children? There are many reasons that can lead to growth hormone deficiency in children. There may be a congenital cause (congenital growth hormone deficiency ), or there may be a birth or postnatal cause of growth hormone deficiency (acquired growth hormone deficiency). Congenital growth hormone deficiency is usually caused by a genetic disorder in which the structure and function of the pituitary gland and hypothalamus are damaged during fetal development. Acquired growth hormone deficiency is caused by damage to the pituitary gland or hypothalamus, which can result from a variety of causes, such as tumors, severe craniocerebral injuries, infections (e.g., meningitis and encephalitis), head irradiation, or surgery. Idiopathic growth hormone deficiency is a growth hormone deficiency with no identified cause.