Growth hormone deficiency is a medical condition in which the pituitary gland does not produce enough growth hormone. Growth hormone is responsible for lateral growth, bone density, muscle mass, body fat, and exercise capacity.
There are several causes, and depending on when it occurs, its effects may result in different growth deficiencies.
Growth Hormone Deficiency In Children
Growth hormone deficiency affects roughly 1 in 4,000-10,000 children. There are 2 classifications of this deficiency: partial and total. Partial growth hormone deficiency means the pituitary gland produces insufficient growth hormone amounts, and total means there no growth hormone production by the pituitary gland.
It may be congenital or it may occur as a result of several medical conditions such as pituitary and hypothalamic tumors and radiotherapy used to overcome childhood cancers. However, many cases are considered idiopathic (unknown).
In newborns, hypoglycemia and physical impairments like micropenis or cleft lip and palate are good indicators there is a problem with the pituitary gland.
Delayed and retarded growth is often a sign of a growth hormone deficiency in older children. More specifically, stunted lateral growth. Children suffering from growth hormone deficiency generally grow less than 2 inches during a year, but this retarded growth may not be prevalent until the child is around 2-3 years of age.
Depending on age and the cause, growth hormone deficiency may delay puberty or may even prevent it from occurring entirely.
According to health professionals, most cases of growth hormone deficiency are not preventable. However, identifying growth hormone deficiency early allows for quick treatment and proactive measures. The quicker the medical condition is caught, “the better chance that a child will grow to be a near-normal adult height.” 
A good way to catch a growth hormone deficiency in its early stage is to meet with a pediatrician, where a physician will measure your child’s development on a growth curve.
Several measurements are generally conducted to officially diagnose growth hormone deficiency in children. These tests and measurements include:
- Insulin-like growth factor (IGF1) measurements
- Stimulation tests
- Additional tests to measure other hormone levels
To treat growth hormone deficiency in children and aid the growth process, injections are given once a day.
Growth Hormone Therapy Risks
Growth hormone therapy for children with growth hormone deficiency rarely results in serious side effects. More common side effects associated with therapy include muscle and joint aches, headaches, fluid retention, and bone slippage at the hip.
Growth Hormone Deficiency In Adults
As adults age, growth hormone production drops as a result. However, this is not the same as growth hormone deficiency.
Although adults may also suffer from growth hormone deficiency, it is considered uncommon. However, adult growth hormone deficiency (AGHD) is becoming more recognized.
There are several ways adults may acquire growth hormone deficiency. According to research, growth hormone deficiencies in adults may be a result of child onset growth hormone deficiency, trauma and injury, or it may be deemed idiopathic.
Researchers indicate adults with growth hormone deficiency as a result of organic childhood GHD is generally “commonly revert to normal GH status.” Adults whose childhood growth hormone deficiency occurs as a result of embryopathic and genetic defects don’t return to normal GH status.
Young adults who suffer from growth hormone deficiency as a result of a medical condition like pituitary surgery and high-dose irradiation damage are said to “commonly revert to normal GH status.” 
Adult-onset idiopathic growth hormone deficiencies are “very rare.” However, growth hormone deficiencies are said to be extremely high in those with multiple pituitary hormone deficiencies (MPHD).
Evidence shows adults with a growth hormone deficiency generally experience relative increases in fat mass and decreases in muscle mass. Also, those suffering from growth hormone deficiency may often experience decreased energy and quality of life.
Growth hormone and its mediator IGF-1 greatly influence body mass and composition. Consequently, lower growth hormone levels increase adipose tissue accrual and result in decreases in muscle mass.
Adult growth hormone deficiency is also associated with neuropsychiatric-cognitive, cardiovascular, neuromuscular, metabolic, and skeletal abnormalities. Though, researchers indicate many of these abnormalities are reversible with therapy.
Growth hormone injections in adults tend to cause more side effects than in children as adults are said to be more susceptible. Despite increased side effect potential, growth hormone therapy is clinically proven to benefit several parameters: 
- Body composition
- Exercise capacity
- Quality of life
According to health professionals, growth hormone doses need to be individualized instead of weight-based. Also, doses should begin low and “be titrated according to clinical response, side effects, and IGF-1 levels.” 
Growth Hormone Therapy Risks
Growth hormone therapy initially resulted in numerous side effects due to the large doses that were administered. Growth hormone doses have since been reduced. Consequently, fewer adverse side effects occur.
Growth hormone therapy has been shown to influence fluid retention and cause carpal tunnel syndrome. Also, patients developed insulin resistance and type-2 diabetes in early clinical studies.
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-  Vishal Gupta. “Adult growth hormone deficiency.” Indian J Endocrinol Metab. 2011 September, 15(suppl3):S197-S202.
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